yield return (イテレーター)
イレテータは、遅延評価の繰り返し処理を簡易にするために使われます。
ただ、このメソッドで戻り値に使う構文は、return文ではなく、yield return文になります。
遅延評価と呼ばれますが、yield returnに到達すると一旦呼び出し元メソッドに戻り、次に呼び出された時に続きを実行するように動作します。
目次
yield returnを含んだコードを逆コンパイルして動作を確認してみる
yield return と foreachを使い、シンプルに構成されたコード
まず、yield returnを使ったサンプルから確認してみましょう。
yield returnに到達するとMainメソッドに戻り次の行が実行されます。
戻り値の型は、IEnumerable<>（型パラメータは、このサンプルでは文字列なのでstring）です。反復評価のためのインターフェースがコンパイラで実装されます。
実行は、MainメソッドとGetStringsメソッドの繰り返しのように見えます。イテレータの部分は遅延評価と呼ばれています。
using System;
using System.Collections.Generic;
class Test
{
// イテレーターを定義
public static IEnumerable<string> GetStrings()
{
yield return "ABC";
yield return "DEF";
yield return "GHI";
}
static void Main()
{
foreach(var str in GetStrings())
{
Console.WriteLine(str);
Console.WriteLine("繰り返し");
}
Console.ReadKey();
}
}実行結果
yield return 文で一度呼び出し側のメソッドに戻ります。
次の呼び出しで、次の行が実行されます。
ABC
繰り返し
DEF
繰り返し
GHI
繰り返しコンパイラーがソースを元に作成するコード（一部加工）
yield return文とforeach文はC#の構文のため、ILで実行するためには、これらのコードを置き換える必要があります。次のコードが逆コンパイラによって変換されたものになります。
このように複雑になりますが、yield returnを使うことで短いコードになりますね。
yield return文とforeach文がないと、switch文を使ったステートマシン（状態管理）が必要になります。yield returnが使えることで、見通しがよくコーディングの効率アップに繋がりますね。
コンパイラが、新たにインナークラスのGetStringsClass（加工）を作成していることも確認しましょう。
using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.Runtime.CompilerServices;
internal class Test
{
[CompilerGenerated]
private sealed class GetStringsClass : IEnumerable<string>, IEnumerable, IEnumerator<string>, IDisposable, IEnumerator
{
private int state;
private string current;
private int initialThreadId;
string IEnumerator<string>.Current
{
[DebuggerHidden]
get
{
return current;
}
}
object IEnumerator.Current
{
[DebuggerHidden]
get
{
return current;
}
}
[DebuggerHidden]
public GetStringsClass(int state)
{
this.state = state;
initialThreadId = Environment.CurrentManagedThreadId;
}
[DebuggerHidden]
void IDisposable.Dispose()
{
}
private bool MoveNext()
{
switch (state)
{
default:
return false;
case 0:
state = -1;
current = "ABC";
state = 1;
return true;
case 1:
state = -1;
current = "DEF";
state = 2;
return true;
case 2:
state = -1;
current = "GHI";
state = 3;
return true;
case 3:
state = -1;
return false;
}
}
bool IEnumerator.MoveNext()
{
//ILSpy generated this explicit interface implementation from .override directive in MoveNext
// ILSpyは、MoveNextの.overrideディレクティブから、この明示的なインターフェイスの実装を生成しました。
return this.MoveNext();
}
[DebuggerHidden]
void IEnumerator.Reset()
{
throw new NotSupportedException();
}
[DebuggerHidden]
IEnumerator<string> IEnumerable<string>.GetEnumerator()
{
if (state == -2 && initialThreadId == Environment.CurrentManagedThreadId)
{
state = 0;
return this;
}
return new GetStringsClass(0);
}
[DebuggerHidden]
IEnumerator IEnumerable.GetEnumerator()
{
return ((IEnumerable<string>)this).GetEnumerator();
}
}
[IteratorStateMachine(typeof(GetStringsClass))]
public static IEnumerable<string> GetStrings()
{
return new GetStringsClass(-2);
}
private static void Main()
{
IEnumerator<string> enumerator = GetStrings().GetEnumerator();
try
{
while (enumerator.MoveNext())
{
string current = enumerator.Current;
Console.WriteLine(current);
Console.WriteLine("繰り返し");
}
}
finally
{
if (enumerator != null)
{
enumerator.Dispose();
}
}
Console.ReadKey();
}
} using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Security;
using System.Security.Permissions;
[assembly: CompilationRelaxations(8)]
[assembly: RuntimeCompatibility(WrapNonExceptionThrows = true)]
[assembly: Debuggable(DebuggableAttribute.DebuggingModes.Default | DebuggableAttribute.DebuggingModes.DisableOptimizations | DebuggableAttribute.DebuggingModes.IgnoreSymbolStoreSequencePoints | DebuggableAttribute.DebuggingModes.EnableEditAndContinue)]
[assembly: SecurityPermission(SecurityAction.RequestMinimum, SkipVerification = true)]
[assembly: AssemblyVersion("0.0.0.0")]
[module: UnverifiableCode]
internal class Test
{
[CompilerGenerated]
private sealed class <GetStrings>d__0 : IEnumerable<string>, IEnumerable, IEnumerator<string>, IDisposable, IEnumerator
{
private int <>1__state;
private string <>2__current;
private int <>l__initialThreadId;
string IEnumerator<string>.Current
{
[DebuggerHidden]
get
{
return <>2__current;
}
}
object IEnumerator.Current
{
[DebuggerHidden]
get
{
return <>2__current;
}
}
[DebuggerHidden]
public <GetStrings>d__0(int <>1__state)
{
this.<>1__state = <>1__state;
<>l__initialThreadId = Environment.CurrentManagedThreadId;
}
[DebuggerHidden]
void IDisposable.Dispose()
{
}
private bool MoveNext()
{
switch (<>1__state)
{
default:
return false;
case 0:
<>1__state = -1;
<>2__current = "ABC";
<>1__state = 1;
return true;
case 1:
<>1__state = -1;
<>2__current = "DEF";
<>1__state = 2;
return true;
case 2:
<>1__state = -1;
<>2__current = "GHI";
<>1__state = 3;
return true;
case 3:
<>1__state = -1;
return false;
}
}
bool IEnumerator.MoveNext()
{
//ILSpy generated this explicit interface implementation from .override directive in MoveNext
return this.MoveNext();
}
[DebuggerHidden]
void IEnumerator.Reset()
{
throw new NotSupportedException();
}
[DebuggerHidden]
IEnumerator<string> IEnumerable<string>.GetEnumerator()
{
if (<>1__state == -2 && <>l__initialThreadId == Environment.CurrentManagedThreadId)
{
<>1__state = 0;
return this;
}
return new <GetStrings>d__0(0);
}
[DebuggerHidden]
IEnumerator IEnumerable.GetEnumerator()
{
return ((IEnumerable<string>)this).GetEnumerator();
}
}
[IteratorStateMachine(typeof(<GetStrings>d__0))]
public static IEnumerable<string> GetStrings()
{
return new <GetStrings>d__0(-2);
}
private static void Main()
{
IEnumerator<string> enumerator = GetStrings().GetEnumerator();
try
{
while (enumerator.MoveNext())
{
string current = enumerator.Current;
Console.WriteLine(current);
Console.WriteLine("繰り返し");
}
}
finally
{
if (enumerator != null)
{
enumerator.Dispose();
}
}
Console.ReadKey();
}
}遅延評価をが行われない（即時実行）クラスの場合（Listクラス）
Listクラスは、イテレータのインターフェースが実装されていますので、foreach文の実行が可能ですが、データはList作成時にキャッシュされるため遅延実行されません。
実際のコードから見てみましょう。
foreachを使い、シンプルに構成されたコード
using System;
using System.Collections.Generic;
class Test
{
static void Main()
{
List<string> Words = new() { "abc", "def", "ghi" };
foreach (var str in Words)
{
Console.WriteLine(str);
Console.WriteLine("繰り返し");
}
Console.ReadKey();
}
}実行結果
abc
繰り返し
def
繰り返し
ghi
繰り返しコンパイラーがソースを元に作成するコード（一部加工）
using System;
using System.Collections.Generic;
internal class Test
{
private static void Main()
{
List<string> list = new List<string>();
list.Add("abc");
list.Add("def");
list.Add("ghi");
List<string> list2 = list;
List<string>.Enumerator enumerator = list2.GetEnumerator();
try
{
while (enumerator.MoveNext())
{
string current = enumerator.Current;
Console.WriteLine(current);
Console.WriteLine("繰り返し");
}
}
finally
{
((IDisposable)enumerator).Dispose();
}
Console.ReadKey();
}
}Listのイテレータ部コード
using System;
using System.Collections;
using System.Collections.Generic;
public class List<T> : IEnumerable<T>, IEnumerable
{
public struct Enumerator : IEnumerator<T>, IEnumerator, IDisposable
{
private T _current;
private object _dummy;
private int _dummyPrimitive;
public T Current
{
get
{
// コード
throw null;
}
}
object? IEnumerator.Current
{
get
{
// コード
throw null;
}
}
public void Dispose()
{
}
public bool MoveNext()
{
// コード
throw null;
}
void IEnumerator.Reset()
{
}
}
IEnumerator<T> IEnumerable<T>.GetEnumerator()
{
// コード
throw null;
}
IEnumerator IEnumerable.GetEnumerator()
{
// コード
throw null;
}
}using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Runtime.CompilerServices;
/// <summary>Represents a strongly typed list of objects that can be accessed by index. Provides methods to search, sort, and manipulate lists.</summary>
/// <typeparam name="T">The type of elements in the list.</typeparam>
public class List<T> : ICollection<T>, IEnumerable<T>, IEnumerable, IList<T>, IReadOnlyCollection<T>, IReadOnlyList<T>, ICollection, IList
{
/// <summary>Enumerates the elements of a <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <typeparam name="T" />
public struct Enumerator : IEnumerator<T>, IEnumerator, IDisposable
{
private T _current;
private object _dummy;
private int _dummyPrimitive;
/// <summary>Gets the element at the current position of the enumerator.</summary>
/// <returns>The element in the <see cref="T:System.Collections.Generic.List`1" /> at the current position of the enumerator.</returns>
public T Current {
[System.Runtime.CompilerServices.NullableContext (1)]
get {
throw null;
}
}
/// <summary>Gets the element at the current position of the enumerator.</summary>
/// <exception cref="T:System.InvalidOperationException">The enumerator is positioned before the first element of the collection or after the last element.</exception>
/// <returns>The element in the <see cref="T:System.Collections.Generic.List`1" /> at the current position of the enumerator.</returns>
object? IEnumerator.Current {
get {
throw null;
}
}
/// <summary>Releases all resources used by the <see cref="T:System.Collections.Generic.List`1.Enumerator" />.</summary>
public void Dispose ()
{
}
/// <summary>Advances the enumerator to the next element of the <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <exception cref="T:System.InvalidOperationException">The collection was modified after the enumerator was created.</exception>
/// <returns>
/// <see langword="true" /> if the enumerator was successfully advanced to the next element; <see langword="false" /> if the enumerator has passed the end of the collection.</returns>
public bool MoveNext ()
{
throw null;
}
/// <summary>Sets the enumerator to its initial position, which is before the first element in the collection.</summary>
/// <exception cref="T:System.InvalidOperationException">The collection was modified after the enumerator was created.</exception>
void IEnumerator.Reset ()
{
}
}
/// <summary>Gets or sets the total number of elements the internal data structure can hold without resizing.</summary>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <see cref="P:System.Collections.Generic.List`1.Capacity" /> is set to a value that is less than <see cref="P:System.Collections.Generic.List`1.Count" />.</exception>
/// <exception cref="T:System.OutOfMemoryException">There is not enough memory available on the system.</exception>
/// <returns>The number of elements that the <see cref="T:System.Collections.Generic.List`1" /> can contain before resizing is required.</returns>
public int Capacity {
get {
throw null;
}
set {
}
}
/// <summary>Gets the number of elements contained in the <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <returns>The number of elements contained in the <see cref="T:System.Collections.Generic.List`1" />.</returns>
public int Count {
get {
throw null;
}
}
/// <summary>Gets or sets the element at the specified index.</summary>
/// <param name="index">The zero-based index of the element to get or set.</param>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is less than 0.
///
/// -or-
///
/// <paramref name="index" /> is equal to or greater than <see cref="P:System.Collections.Generic.List`1.Count" />.</exception>
/// <returns>The element at the specified index.</returns>
public T this [int index] {
get {
throw null;
}
set {
}
}
/// <summary>Gets a value indicating whether the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only.</summary>
/// <returns>
/// <see langword="true" /> if the <see cref="T:System.Collections.Generic.ICollection`1" /> is read-only; otherwise, <see langword="false" />. In the default implementation of <see cref="T:System.Collections.Generic.List`1" />, this property always returns <see langword="false" />.</returns>
bool ICollection<T>.IsReadOnly {
get {
throw null;
}
}
/// <summary>Gets a value indicating whether access to the <see cref="T:System.Collections.ICollection" /> is synchronized (thread safe).</summary>
/// <returns>
/// <see langword="true" /> if access to the <see cref="T:System.Collections.ICollection" /> is synchronized (thread safe); otherwise, <see langword="false" />. In the default implementation of <see cref="T:System.Collections.Generic.List`1" />, this property always returns <see langword="false" />.</returns>
bool ICollection.IsSynchronized {
get {
throw null;
}
}
/// <summary>Gets an object that can be used to synchronize access to the <see cref="T:System.Collections.ICollection" />.</summary>
/// <returns>An object that can be used to synchronize access to the <see cref="T:System.Collections.ICollection" />. In the default implementation of <see cref="T:System.Collections.Generic.List`1" />, this property always returns the current instance.</returns>
object ICollection.SyncRoot {
get {
throw null;
}
}
/// <summary>Gets a value indicating whether the <see cref="T:System.Collections.IList" /> has a fixed size.</summary>
/// <returns>
/// <see langword="true" /> if the <see cref="T:System.Collections.IList" /> has a fixed size; otherwise, <see langword="false" />. In the default implementation of <see cref="T:System.Collections.Generic.List`1" />, this property always returns <see langword="false" />.</returns>
bool IList.IsFixedSize {
get {
throw null;
}
}
/// <summary>Gets a value indicating whether the <see cref="T:System.Collections.IList" /> is read-only.</summary>
/// <returns>
/// <see langword="true" /> if the <see cref="T:System.Collections.IList" /> is read-only; otherwise, <see langword="false" />. In the default implementation of <see cref="T:System.Collections.Generic.List`1" />, this property always returns <see langword="false" />.</returns>
bool IList.IsReadOnly {
get {
throw null;
}
}
/// <summary>Gets or sets the element at the specified index.</summary>
/// <param name="index">The zero-based index of the element to get or set.</param>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is not a valid index in the <see cref="T:System.Collections.IList" />.</exception>
/// <exception cref="T:System.ArgumentException">The property is set and <paramref name="value" /> is of a type that is not assignable to the <see cref="T:System.Collections.IList" />.</exception>
/// <returns>The element at the specified index.</returns>
object? IList.this [int index] {
get {
throw null;
}
set {
}
}
/// <summary>Initializes a new instance of the <see cref="T:System.Collections.Generic.List`1" /> class that is empty and has the default initial capacity.</summary>
public List ()
{
}
/// <summary>Initializes a new instance of the <see cref="T:System.Collections.Generic.List`1" /> class that contains elements copied from the specified collection and has sufficient capacity to accommodate the number of elements copied.</summary>
/// <param name="collection">The collection whose elements are copied to the new list.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="collection" /> is <see langword="null" />.</exception>
public List (IEnumerable<T> collection)
{
}
/// <summary>Initializes a new instance of the <see cref="T:System.Collections.Generic.List`1" /> class that is empty and has the specified initial capacity.</summary>
/// <param name="capacity">The number of elements that the new list can initially store.</param>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="capacity" /> is less than 0.</exception>
public List (int capacity)
{
}
/// <summary>Adds an object to the end of the <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <param name="item">The object to be added to the end of the <see cref="T:System.Collections.Generic.List`1" />. The value can be <see langword="null" /> for reference types.</param>
public void Add (T item)
{
}
/// <summary>Adds the elements of the specified collection to the end of the <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <param name="collection">The collection whose elements should be added to the end of the <see cref="T:System.Collections.Generic.List`1" />. The collection itself cannot be <see langword="null" />, but it can contain elements that are <see langword="null" />, if type <paramref name="T" /> is a reference type.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="collection" /> is <see langword="null" />.</exception>
public void AddRange (IEnumerable<T> collection)
{
}
/// <summary>Returns a read-only <see cref="T:System.Collections.ObjectModel.ReadOnlyCollection`1" /> wrapper for the current collection.</summary>
/// <returns>An object that acts as a read-only wrapper around the current <see cref="T:System.Collections.Generic.List`1" />.</returns>
public ReadOnlyCollection<T> AsReadOnly ()
{
throw null;
}
/// <summary>Searches a range of elements in the sorted <see cref="T:System.Collections.Generic.List`1" /> for an element using the specified comparer and returns the zero-based index of the element.</summary>
/// <param name="index">The zero-based starting index of the range to search.</param>
/// <param name="count">The length of the range to search.</param>
/// <param name="item">The object to locate. The value can be <see langword="null" /> for reference types.</param>
/// <param name="comparer">The <see cref="T:System.Collections.Generic.IComparer`1" /> implementation to use when comparing elements, or <see langword="null" /> to use the default comparer <see cref="P:System.Collections.Generic.Comparer`1.Default" />.</param>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is less than 0.
///
/// -or-
///
/// <paramref name="count" /> is less than 0.</exception>
/// <exception cref="T:System.ArgumentException">
/// <paramref name="index" /> and <paramref name="count" /> do not denote a valid range in the <see cref="T:System.Collections.Generic.List`1" />.</exception>
/// <exception cref="T:System.InvalidOperationException">
/// <paramref name="comparer" /> is <see langword="null" />, and the default comparer <see cref="P:System.Collections.Generic.Comparer`1.Default" /> cannot find an implementation of the <see cref="T:System.IComparable`1" /> generic interface or the <see cref="T:System.IComparable" /> interface for type <paramref name="T" />.</exception>
/// <returns>The zero-based index of <paramref name="item" /> in the sorted <see cref="T:System.Collections.Generic.List`1" />, if <paramref name="item" /> is found; otherwise, a negative number that is the bitwise complement of the index of the next element that is larger than <paramref name="item" /> or, if there is no larger element, the bitwise complement of <see cref="P:System.Collections.Generic.List`1.Count" />.</returns>
public int BinarySearch (int index, int count, T item, IComparer<T>? comparer)
{
throw null;
}
/// <summary>Searches the entire sorted <see cref="T:System.Collections.Generic.List`1" /> for an element using the default comparer and returns the zero-based index of the element.</summary>
/// <param name="item">The object to locate. The value can be <see langword="null" /> for reference types.</param>
/// <exception cref="T:System.InvalidOperationException">The default comparer <see cref="P:System.Collections.Generic.Comparer`1.Default" /> cannot find an implementation of the <see cref="T:System.IComparable`1" /> generic interface or the <see cref="T:System.IComparable" /> interface for type <paramref name="T" />.</exception>
/// <returns>The zero-based index of <paramref name="item" /> in the sorted <see cref="T:System.Collections.Generic.List`1" />, if <paramref name="item" /> is found; otherwise, a negative number that is the bitwise complement of the index of the next element that is larger than <paramref name="item" /> or, if there is no larger element, the bitwise complement of <see cref="P:System.Collections.Generic.List`1.Count" />.</returns>
public int BinarySearch (T item)
{
throw null;
}
/// <summary>Searches the entire sorted <see cref="T:System.Collections.Generic.List`1" /> for an element using the specified comparer and returns the zero-based index of the element.</summary>
/// <param name="item">The object to locate. The value can be <see langword="null" /> for reference types.</param>
/// <param name="comparer">The <see cref="T:System.Collections.Generic.IComparer`1" /> implementation to use when comparing elements.
///
/// -or-
///
/// <see langword="null" /> to use the default comparer <see cref="P:System.Collections.Generic.Comparer`1.Default" />.</param>
/// <exception cref="T:System.InvalidOperationException">
/// <paramref name="comparer" /> is <see langword="null" />, and the default comparer <see cref="P:System.Collections.Generic.Comparer`1.Default" /> cannot find an implementation of the <see cref="T:System.IComparable`1" /> generic interface or the <see cref="T:System.IComparable" /> interface for type <paramref name="T" />.</exception>
/// <returns>The zero-based index of <paramref name="item" /> in the sorted <see cref="T:System.Collections.Generic.List`1" />, if <paramref name="item" /> is found; otherwise, a negative number that is the bitwise complement of the index of the next element that is larger than <paramref name="item" /> or, if there is no larger element, the bitwise complement of <see cref="P:System.Collections.Generic.List`1.Count" />.</returns>
public int BinarySearch (T item, IComparer<T>? comparer)
{
throw null;
}
/// <summary>Removes all elements from the <see cref="T:System.Collections.Generic.List`1" />.</summary>
public void Clear ()
{
}
/// <summary>Determines whether an element is in the <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <param name="item">The object to locate in the <see cref="T:System.Collections.Generic.List`1" />. The value can be <see langword="null" /> for reference types.</param>
/// <returns>
/// <see langword="true" /> if <paramref name="item" /> is found in the <see cref="T:System.Collections.Generic.List`1" />; otherwise, <see langword="false" />.</returns>
public bool Contains (T item)
{
throw null;
}
/// <summary>Converts the elements in the current <see cref="T:System.Collections.Generic.List`1" /> to another type, and returns a list containing the converted elements.</summary>
/// <param name="converter">A <see cref="T:System.Converter`2" /> delegate that converts each element from one type to another type.</param>
/// <typeparam name="TOutput">The type of the elements of the target array.</typeparam>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="converter" /> is <see langword="null" />.</exception>
/// <returns>A <see cref="T:System.Collections.Generic.List`1" /> of the target type containing the converted elements from the current <see cref="T:System.Collections.Generic.List`1" />.</returns>
public List<TOutput> ConvertAll<TOutput> (Converter<T, TOutput> converter)
{
throw null;
}
/// <summary>Copies a range of elements from the <see cref="T:System.Collections.Generic.List`1" /> to a compatible one-dimensional array, starting at the specified index of the target array.</summary>
/// <param name="index">The zero-based index in the source <see cref="T:System.Collections.Generic.List`1" /> at which copying begins.</param>
/// <param name="array">The one-dimensional <see cref="T:System.Array" /> that is the destination of the elements copied from <see cref="T:System.Collections.Generic.List`1" />. The <see cref="T:System.Array" /> must have zero-based indexing.</param>
/// <param name="arrayIndex">The zero-based index in <paramref name="array" /> at which copying begins.</param>
/// <param name="count">The number of elements to copy.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="array" /> is <see langword="null" />.</exception>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is less than 0.
///
/// -or-
///
/// <paramref name="arrayIndex" /> is less than 0.
///
/// -or-
///
/// <paramref name="count" /> is less than 0.</exception>
/// <exception cref="T:System.ArgumentException">
/// <paramref name="index" /> is equal to or greater than the <see cref="P:System.Collections.Generic.List`1.Count" /> of the source <see cref="T:System.Collections.Generic.List`1" />.
///
/// -or-
///
/// The number of elements from <paramref name="index" /> to the end of the source <see cref="T:System.Collections.Generic.List`1" /> is greater than the available space from <paramref name="arrayIndex" /> to the end of the destination <paramref name="array" />.</exception>
public void CopyTo (int index, T[] array, int arrayIndex, int count)
{
}
/// <summary>Copies the entire <see cref="T:System.Collections.Generic.List`1" /> to a compatible one-dimensional array, starting at the beginning of the target array.</summary>
/// <param name="array">The one-dimensional <see cref="T:System.Array" /> that is the destination of the elements copied from <see cref="T:System.Collections.Generic.List`1" />. The <see cref="T:System.Array" /> must have zero-based indexing.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="array" /> is <see langword="null" />.</exception>
/// <exception cref="T:System.ArgumentException">The number of elements in the source <see cref="T:System.Collections.Generic.List`1" /> is greater than the number of elements that the destination <paramref name="array" /> can contain.</exception>
public void CopyTo (T[] array)
{
}
/// <summary>Copies the entire <see cref="T:System.Collections.Generic.List`1" /> to a compatible one-dimensional array, starting at the specified index of the target array.</summary>
/// <param name="array">The one-dimensional <see cref="T:System.Array" /> that is the destination of the elements copied from <see cref="T:System.Collections.Generic.List`1" />. The <see cref="T:System.Array" /> must have zero-based indexing.</param>
/// <param name="arrayIndex">The zero-based index in <paramref name="array" /> at which copying begins.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="array" /> is <see langword="null" />.</exception>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="arrayIndex" /> is less than 0.</exception>
/// <exception cref="T:System.ArgumentException">The number of elements in the source <see cref="T:System.Collections.Generic.List`1" /> is greater than the available space from <paramref name="arrayIndex" /> to the end of the destination <paramref name="array" />.</exception>
public void CopyTo (T[] array, int arrayIndex)
{
}
/// <summary>Determines whether the <see cref="T:System.Collections.Generic.List`1" /> contains elements that match the conditions defined by the specified predicate.</summary>
/// <param name="match">The <see cref="T:System.Predicate`1" /> delegate that defines the conditions of the elements to search for.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="match" /> is <see langword="null" />.</exception>
/// <returns>
/// <see langword="true" /> if the <see cref="T:System.Collections.Generic.List`1" /> contains one or more elements that match the conditions defined by the specified predicate; otherwise, <see langword="false" />.</returns>
public bool Exists (Predicate<T> match)
{
throw null;
}
/// <summary>Searches for an element that matches the conditions defined by the specified predicate, and returns the first occurrence within the entire <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <param name="match">The <see cref="T:System.Predicate`1" /> delegate that defines the conditions of the element to search for.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="match" /> is <see langword="null" />.</exception>
/// <returns>The first element that matches the conditions defined by the specified predicate, if found; otherwise, the default value for type <paramref name="T" />.</returns>
public T? Find (Predicate<T> match)
{
throw null;
}
/// <summary>Retrieves all the elements that match the conditions defined by the specified predicate.</summary>
/// <param name="match">The <see cref="T:System.Predicate`1" /> delegate that defines the conditions of the elements to search for.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="match" /> is <see langword="null" />.</exception>
/// <returns>A <see cref="T:System.Collections.Generic.List`1" /> containing all the elements that match the conditions defined by the specified predicate, if found; otherwise, an empty <see cref="T:System.Collections.Generic.List`1" />.</returns>
public List<T> FindAll (Predicate<T> match)
{
throw null;
}
/// <summary>Searches for an element that matches the conditions defined by the specified predicate, and returns the zero-based index of the first occurrence within the range of elements in the <see cref="T:System.Collections.Generic.List`1" /> that starts at the specified index and contains the specified number of elements.</summary>
/// <param name="startIndex">The zero-based starting index of the search.</param>
/// <param name="count">The number of elements in the section to search.</param>
/// <param name="match">The <see cref="T:System.Predicate`1" /> delegate that defines the conditions of the element to search for.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="match" /> is <see langword="null" />.</exception>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="startIndex" /> is outside the range of valid indexes for the <see cref="T:System.Collections.Generic.List`1" />.
///
/// -or-
///
/// <paramref name="count" /> is less than 0.
///
/// -or-
///
/// <paramref name="startIndex" /> and <paramref name="count" /> do not specify a valid section in the <see cref="T:System.Collections.Generic.List`1" />.</exception>
/// <returns>The zero-based index of the first occurrence of an element that matches the conditions defined by <paramref name="match" />, if found; otherwise, -1.</returns>
public int FindIndex (int startIndex, int count, Predicate<T> match)
{
throw null;
}
/// <summary>Searches for an element that matches the conditions defined by the specified predicate, and returns the zero-based index of the first occurrence within the range of elements in the <see cref="T:System.Collections.Generic.List`1" /> that extends from the specified index to the last element.</summary>
/// <param name="startIndex">The zero-based starting index of the search.</param>
/// <param name="match">The <see cref="T:System.Predicate`1" /> delegate that defines the conditions of the element to search for.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="match" /> is <see langword="null" />.</exception>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="startIndex" /> is outside the range of valid indexes for the <see cref="T:System.Collections.Generic.List`1" />.</exception>
/// <returns>The zero-based index of the first occurrence of an element that matches the conditions defined by <paramref name="match" />, if found; otherwise, -1.</returns>
public int FindIndex (int startIndex, Predicate<T> match)
{
throw null;
}
/// <summary>Searches for an element that matches the conditions defined by the specified predicate, and returns the zero-based index of the first occurrence within the entire <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <param name="match">The <see cref="T:System.Predicate`1" /> delegate that defines the conditions of the element to search for.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="match" /> is <see langword="null" />.</exception>
/// <returns>The zero-based index of the first occurrence of an element that matches the conditions defined by <paramref name="match" />, if found; otherwise, -1.</returns>
public int FindIndex (Predicate<T> match)
{
throw null;
}
/// <summary>Searches for an element that matches the conditions defined by the specified predicate, and returns the last occurrence within the entire <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <param name="match">The <see cref="T:System.Predicate`1" /> delegate that defines the conditions of the element to search for.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="match" /> is <see langword="null" />.</exception>
/// <returns>The last element that matches the conditions defined by the specified predicate, if found; otherwise, the default value for type <paramref name="T" />.</returns>
public T? FindLast (Predicate<T> match)
{
throw null;
}
/// <summary>Searches for an element that matches the conditions defined by the specified predicate, and returns the zero-based index of the last occurrence within the range of elements in the <see cref="T:System.Collections.Generic.List`1" /> that contains the specified number of elements and ends at the specified index.</summary>
/// <param name="startIndex">The zero-based starting index of the backward search.</param>
/// <param name="count">The number of elements in the section to search.</param>
/// <param name="match">The <see cref="T:System.Predicate`1" /> delegate that defines the conditions of the element to search for.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="match" /> is <see langword="null" />.</exception>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="startIndex" /> is outside the range of valid indexes for the <see cref="T:System.Collections.Generic.List`1" />.
///
/// -or-
///
/// <paramref name="count" /> is less than 0.
///
/// -or-
///
/// <paramref name="startIndex" /> and <paramref name="count" /> do not specify a valid section in the <see cref="T:System.Collections.Generic.List`1" />.</exception>
/// <returns>The zero-based index of the last occurrence of an element that matches the conditions defined by <paramref name="match" />, if found; otherwise, -1.</returns>
public int FindLastIndex (int startIndex, int count, Predicate<T> match)
{
throw null;
}
/// <summary>Searches for an element that matches the conditions defined by the specified predicate, and returns the zero-based index of the last occurrence within the range of elements in the <see cref="T:System.Collections.Generic.List`1" /> that extends from the first element to the specified index.</summary>
/// <param name="startIndex">The zero-based starting index of the backward search.</param>
/// <param name="match">The <see cref="T:System.Predicate`1" /> delegate that defines the conditions of the element to search for.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="match" /> is <see langword="null" />.</exception>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="startIndex" /> is outside the range of valid indexes for the <see cref="T:System.Collections.Generic.List`1" />.</exception>
/// <returns>The zero-based index of the last occurrence of an element that matches the conditions defined by <paramref name="match" />, if found; otherwise, -1.</returns>
public int FindLastIndex (int startIndex, Predicate<T> match)
{
throw null;
}
/// <summary>Searches for an element that matches the conditions defined by the specified predicate, and returns the zero-based index of the last occurrence within the entire <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <param name="match">The <see cref="T:System.Predicate`1" /> delegate that defines the conditions of the element to search for.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="match" /> is <see langword="null" />.</exception>
/// <returns>The zero-based index of the last occurrence of an element that matches the conditions defined by <paramref name="match" />, if found; otherwise, -1.</returns>
public int FindLastIndex (Predicate<T> match)
{
throw null;
}
/// <summary>Performs the specified action on each element of the <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <param name="action">The <see cref="T:System.Action`1" /> delegate to perform on each element of the <see cref="T:System.Collections.Generic.List`1" />.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="action" /> is <see langword="null" />.</exception>
/// <exception cref="T:System.InvalidOperationException">An element in the collection has been modified.</exception>
public void ForEach (Action<T> action)
{
}
/// <summary>Returns an enumerator that iterates through the <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <returns>A <see cref="T:System.Collections.Generic.List`1.Enumerator" /> for the <see cref="T:System.Collections.Generic.List`1" />.</returns>
public List<T>.Enumerator GetEnumerator ()
{
throw null;
}
/// <summary>Creates a shallow copy of a range of elements in the source <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <param name="index">The zero-based <see cref="T:System.Collections.Generic.List`1" /> index at which the range starts.</param>
/// <param name="count">The number of elements in the range.</param>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is less than 0.
///
/// -or-
///
/// <paramref name="count" /> is less than 0.</exception>
/// <exception cref="T:System.ArgumentException">
/// <paramref name="index" /> and <paramref name="count" /> do not denote a valid range of elements in the <see cref="T:System.Collections.Generic.List`1" />.</exception>
/// <returns>A shallow copy of a range of elements in the source <see cref="T:System.Collections.Generic.List`1" />.</returns>
public List<T> GetRange (int index, int count)
{
throw null;
}
/// <summary>Searches for the specified object and returns the zero-based index of the first occurrence within the entire <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <param name="item">The object to locate in the <see cref="T:System.Collections.Generic.List`1" />. The value can be <see langword="null" /> for reference types.</param>
/// <returns>The zero-based index of the first occurrence of <paramref name="item" /> within the entire <see cref="T:System.Collections.Generic.List`1" />, if found; otherwise, -1.</returns>
public int IndexOf (T item)
{
throw null;
}
/// <summary>Searches for the specified object and returns the zero-based index of the first occurrence within the range of elements in the <see cref="T:System.Collections.Generic.List`1" /> that extends from the specified index to the last element.</summary>
/// <param name="item">The object to locate in the <see cref="T:System.Collections.Generic.List`1" />. The value can be <see langword="null" /> for reference types.</param>
/// <param name="index">The zero-based starting index of the search. 0 (zero) is valid in an empty list.</param>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is outside the range of valid indexes for the <see cref="T:System.Collections.Generic.List`1" />.</exception>
/// <returns>The zero-based index of the first occurrence of <paramref name="item" /> within the range of elements in the <see cref="T:System.Collections.Generic.List`1" /> that extends from <paramref name="index" /> to the last element, if found; otherwise, -1.</returns>
public int IndexOf (T item, int index)
{
throw null;
}
/// <summary>Searches for the specified object and returns the zero-based index of the first occurrence within the range of elements in the <see cref="T:System.Collections.Generic.List`1" /> that starts at the specified index and contains the specified number of elements.</summary>
/// <param name="item">The object to locate in the <see cref="T:System.Collections.Generic.List`1" />. The value can be <see langword="null" /> for reference types.</param>
/// <param name="index">The zero-based starting index of the search. 0 (zero) is valid in an empty list.</param>
/// <param name="count">The number of elements in the section to search.</param>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is outside the range of valid indexes for the <see cref="T:System.Collections.Generic.List`1" />.
///
/// -or-
///
/// <paramref name="count" /> is less than 0.
///
/// -or-
///
/// <paramref name="index" /> and <paramref name="count" /> do not specify a valid section in the <see cref="T:System.Collections.Generic.List`1" />.</exception>
/// <returns>The zero-based index of the first occurrence of <paramref name="item" /> within the range of elements in the <see cref="T:System.Collections.Generic.List`1" /> that starts at <paramref name="index" /> and contains <paramref name="count" /> number of elements, if found; otherwise, -1.</returns>
public int IndexOf (T item, int index, int count)
{
throw null;
}
/// <summary>Inserts an element into the <see cref="T:System.Collections.Generic.List`1" /> at the specified index.</summary>
/// <param name="index">The zero-based index at which <paramref name="item" /> should be inserted.</param>
/// <param name="item">The object to insert. The value can be <see langword="null" /> for reference types.</param>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is less than 0.
///
/// -or-
///
/// <paramref name="index" /> is greater than <see cref="P:System.Collections.Generic.List`1.Count" />.</exception>
public void Insert (int index, T item)
{
}
/// <summary>Inserts the elements of a collection into the <see cref="T:System.Collections.Generic.List`1" /> at the specified index.</summary>
/// <param name="index">The zero-based index at which the new elements should be inserted.</param>
/// <param name="collection">The collection whose elements should be inserted into the <see cref="T:System.Collections.Generic.List`1" />. The collection itself cannot be <see langword="null" />, but it can contain elements that are <see langword="null" />, if type <paramref name="T" /> is a reference type.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="collection" /> is <see langword="null" />.</exception>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is less than 0.
///
/// -or-
///
/// <paramref name="index" /> is greater than <see cref="P:System.Collections.Generic.List`1.Count" />.</exception>
public void InsertRange (int index, IEnumerable<T> collection)
{
}
/// <summary>Searches for the specified object and returns the zero-based index of the last occurrence within the entire <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <param name="item">The object to locate in the <see cref="T:System.Collections.Generic.List`1" />. The value can be <see langword="null" /> for reference types.</param>
/// <returns>The zero-based index of the last occurrence of <paramref name="item" /> within the entire the <see cref="T:System.Collections.Generic.List`1" />, if found; otherwise, -1.</returns>
public int LastIndexOf (T item)
{
throw null;
}
/// <summary>Searches for the specified object and returns the zero-based index of the last occurrence within the range of elements in the <see cref="T:System.Collections.Generic.List`1" /> that extends from the first element to the specified index.</summary>
/// <param name="item">The object to locate in the <see cref="T:System.Collections.Generic.List`1" />. The value can be <see langword="null" /> for reference types.</param>
/// <param name="index">The zero-based starting index of the backward search.</param>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is outside the range of valid indexes for the <see cref="T:System.Collections.Generic.List`1" />.</exception>
/// <returns>The zero-based index of the last occurrence of <paramref name="item" /> within the range of elements in the <see cref="T:System.Collections.Generic.List`1" /> that extends from the first element to <paramref name="index" />, if found; otherwise, -1.</returns>
public int LastIndexOf (T item, int index)
{
throw null;
}
/// <summary>Searches for the specified object and returns the zero-based index of the last occurrence within the range of elements in the <see cref="T:System.Collections.Generic.List`1" /> that contains the specified number of elements and ends at the specified index.</summary>
/// <param name="item">The object to locate in the <see cref="T:System.Collections.Generic.List`1" />. The value can be <see langword="null" /> for reference types.</param>
/// <param name="index">The zero-based starting index of the backward search.</param>
/// <param name="count">The number of elements in the section to search.</param>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is outside the range of valid indexes for the <see cref="T:System.Collections.Generic.List`1" />.
///
/// -or-
///
/// <paramref name="count" /> is less than 0.
///
/// -or-
///
/// <paramref name="index" /> and <paramref name="count" /> do not specify a valid section in the <see cref="T:System.Collections.Generic.List`1" />.</exception>
/// <returns>The zero-based index of the last occurrence of <paramref name="item" /> within the range of elements in the <see cref="T:System.Collections.Generic.List`1" /> that contains <paramref name="count" /> number of elements and ends at <paramref name="index" />, if found; otherwise, -1.</returns>
public int LastIndexOf (T item, int index, int count)
{
throw null;
}
/// <summary>Removes the first occurrence of a specific object from the <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <param name="item">The object to remove from the <see cref="T:System.Collections.Generic.List`1" />. The value can be <see langword="null" /> for reference types.</param>
/// <returns>
/// <see langword="true" /> if <paramref name="item" /> is successfully removed; otherwise, <see langword="false" />. This method also returns <see langword="false" /> if <paramref name="item" /> was not found in the <see cref="T:System.Collections.Generic.List`1" />.</returns>
public bool Remove (T item)
{
throw null;
}
/// <summary>Removes all the elements that match the conditions defined by the specified predicate.</summary>
/// <param name="match">The <see cref="T:System.Predicate`1" /> delegate that defines the conditions of the elements to remove.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="match" /> is <see langword="null" />.</exception>
/// <returns>The number of elements removed from the <see cref="T:System.Collections.Generic.List`1" />.</returns>
public int RemoveAll (Predicate<T> match)
{
throw null;
}
/// <summary>Removes the element at the specified index of the <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <param name="index">The zero-based index of the element to remove.</param>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is less than 0.
///
/// -or-
///
/// <paramref name="index" /> is equal to or greater than <see cref="P:System.Collections.Generic.List`1.Count" />.</exception>
public void RemoveAt (int index)
{
}
/// <summary>Removes a range of elements from the <see cref="T:System.Collections.Generic.List`1" />.</summary>
/// <param name="index">The zero-based starting index of the range of elements to remove.</param>
/// <param name="count">The number of elements to remove.</param>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is less than 0.
///
/// -or-
///
/// <paramref name="count" /> is less than 0.</exception>
/// <exception cref="T:System.ArgumentException">
/// <paramref name="index" /> and <paramref name="count" /> do not denote a valid range of elements in the <see cref="T:System.Collections.Generic.List`1" />.</exception>
public void RemoveRange (int index, int count)
{
}
/// <summary>Reverses the order of the elements in the entire <see cref="T:System.Collections.Generic.List`1" />.</summary>
public void Reverse ()
{
}
/// <summary>Reverses the order of the elements in the specified range.</summary>
/// <param name="index">The zero-based starting index of the range to reverse.</param>
/// <param name="count">The number of elements in the range to reverse.</param>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is less than 0.
///
/// -or-
///
/// <paramref name="count" /> is less than 0.</exception>
/// <exception cref="T:System.ArgumentException">
/// <paramref name="index" /> and <paramref name="count" /> do not denote a valid range of elements in the <see cref="T:System.Collections.Generic.List`1" />.</exception>
public void Reverse (int index, int count)
{
}
/// <summary>Sorts the elements in the entire <see cref="T:System.Collections.Generic.List`1" /> using the default comparer.</summary>
/// <exception cref="T:System.InvalidOperationException">The default comparer <see cref="P:System.Collections.Generic.Comparer`1.Default" /> cannot find an implementation of the <see cref="T:System.IComparable`1" /> generic interface or the <see cref="T:System.IComparable" /> interface for type <paramref name="T" />.</exception>
public void Sort ()
{
}
/// <summary>Sorts the elements in the entire <see cref="T:System.Collections.Generic.List`1" /> using the specified comparer.</summary>
/// <param name="comparer">The <see cref="T:System.Collections.Generic.IComparer`1" /> implementation to use when comparing elements, or <see langword="null" /> to use the default comparer <see cref="P:System.Collections.Generic.Comparer`1.Default" />.</param>
/// <exception cref="T:System.InvalidOperationException">
/// <paramref name="comparer" /> is <see langword="null" />, and the default comparer <see cref="P:System.Collections.Generic.Comparer`1.Default" /> cannot find implementation of the <see cref="T:System.IComparable`1" /> generic interface or the <see cref="T:System.IComparable" /> interface for type <paramref name="T" />.</exception>
/// <exception cref="T:System.ArgumentException">The implementation of <paramref name="comparer" /> caused an error during the sort. For example, <paramref name="comparer" /> might not return 0 when comparing an item with itself.</exception>
public void Sort (IComparer<T>? comparer)
{
}
/// <summary>Sorts the elements in the entire <see cref="T:System.Collections.Generic.List`1" /> using the specified <see cref="T:System.Comparison`1" />.</summary>
/// <param name="comparison">The <see cref="T:System.Comparison`1" /> to use when comparing elements.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="comparison" /> is <see langword="null" />.</exception>
/// <exception cref="T:System.ArgumentException">The implementation of <paramref name="comparison" /> caused an error during the sort. For example, <paramref name="comparison" /> might not return 0 when comparing an item with itself.</exception>
public void Sort (Comparison<T> comparison)
{
}
/// <summary>Sorts the elements in a range of elements in <see cref="T:System.Collections.Generic.List`1" /> using the specified comparer.</summary>
/// <param name="index">The zero-based starting index of the range to sort.</param>
/// <param name="count">The length of the range to sort.</param>
/// <param name="comparer">The <see cref="T:System.Collections.Generic.IComparer`1" /> implementation to use when comparing elements, or <see langword="null" /> to use the default comparer <see cref="P:System.Collections.Generic.Comparer`1.Default" />.</param>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is less than 0.
///
/// -or-
///
/// <paramref name="count" /> is less than 0.</exception>
/// <exception cref="T:System.ArgumentException">
/// <paramref name="index" /> and <paramref name="count" /> do not specify a valid range in the <see cref="T:System.Collections.Generic.List`1" />.
///
/// -or-
///
/// The implementation of <paramref name="comparer" /> caused an error during the sort. For example, <paramref name="comparer" /> might not return 0 when comparing an item with itself.</exception>
/// <exception cref="T:System.InvalidOperationException">
/// <paramref name="comparer" /> is <see langword="null" />, and the default comparer <see cref="P:System.Collections.Generic.Comparer`1.Default" /> cannot find implementation of the <see cref="T:System.IComparable`1" /> generic interface or the <see cref="T:System.IComparable" /> interface for type <paramref name="T" />.</exception>
public void Sort (int index, int count, IComparer<T>? comparer)
{
}
/// <summary>Returns an enumerator that iterates through a collection.</summary>
/// <returns>An <see cref="T:System.Collections.Generic.IEnumerator`1" /> that can be used to iterate through the collection.</returns>
IEnumerator<T> IEnumerable<T>.GetEnumerator ()
{
throw null;
}
/// <summary>Copies the elements of the <see cref="T:System.Collections.ICollection" /> to an <see cref="T:System.Array" />, starting at a particular <see cref="T:System.Array" /> index.</summary>
/// <param name="array">The one-dimensional <see cref="T:System.Array" /> that is the destination of the elements copied from <see cref="T:System.Collections.ICollection" />. The <see cref="T:System.Array" /> must have zero-based indexing.</param>
/// <param name="arrayIndex">The zero-based index in <paramref name="array" /> at which copying begins.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="array" /> is <see langword="null" />.</exception>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="arrayIndex" /> is less than 0.</exception>
/// <exception cref="T:System.ArgumentException">
/// <paramref name="array" /> is multidimensional.
///
/// -or-
///
/// <paramref name="array" /> does not have zero-based indexing.
///
/// -or-
///
/// The number of elements in the source <see cref="T:System.Collections.ICollection" /> is greater than the available space from <paramref name="arrayIndex" /> to the end of the destination <paramref name="array" />.
///
/// -or-
///
/// The type of the source <see cref="T:System.Collections.ICollection" /> cannot be cast automatically to the type of the destination <paramref name="array" />.</exception>
void ICollection.CopyTo (Array array, int arrayIndex)
{
}
/// <summary>Returns an enumerator that iterates through a collection.</summary>
/// <returns>An <see cref="T:System.Collections.IEnumerator" /> that can be used to iterate through the collection.</returns>
IEnumerator IEnumerable.GetEnumerator ()
{
throw null;
}
/// <summary>Adds an item to the <see cref="T:System.Collections.IList" />.</summary>
/// <param name="item">The <see cref="T:System.Object" /> to add to the <see cref="T:System.Collections.IList" />.</param>
/// <exception cref="T:System.ArgumentException">
/// <paramref name="item" /> is of a type that is not assignable to the <see cref="T:System.Collections.IList" />.</exception>
/// <returns>The position into which the new element was inserted.</returns>
int IList.Add (object item)
{
throw null;
}
/// <summary>Determines whether the <see cref="T:System.Collections.IList" /> contains a specific value.</summary>
/// <param name="item">The <see cref="T:System.Object" /> to locate in the <see cref="T:System.Collections.IList" />.</param>
/// <returns>
/// <see langword="true" /> if <paramref name="item" /> is found in the <see cref="T:System.Collections.IList" />; otherwise, <see langword="false" />.</returns>
bool IList.Contains (object item)
{
throw null;
}
/// <summary>Determines the index of a specific item in the <see cref="T:System.Collections.IList" />.</summary>
/// <param name="item">The object to locate in the <see cref="T:System.Collections.IList" />.</param>
/// <exception cref="T:System.ArgumentException">
/// <paramref name="item" /> is of a type that is not assignable to the <see cref="T:System.Collections.IList" />.</exception>
/// <returns>The index of <paramref name="item" /> if found in the list; otherwise, -1.</returns>
int IList.IndexOf (object item)
{
throw null;
}
/// <summary>Inserts an item to the <see cref="T:System.Collections.IList" /> at the specified index.</summary>
/// <param name="index">The zero-based index at which <paramref name="item" /> should be inserted.</param>
/// <param name="item">The object to insert into the <see cref="T:System.Collections.IList" />.</param>
/// <exception cref="T:System.ArgumentOutOfRangeException">
/// <paramref name="index" /> is not a valid index in the <see cref="T:System.Collections.IList" />.</exception>
/// <exception cref="T:System.ArgumentException">
/// <paramref name="item" /> is of a type that is not assignable to the <see cref="T:System.Collections.IList" />.</exception>
void IList.Insert (int index, object item)
{
}
/// <summary>Removes the first occurrence of a specific object from the <see cref="T:System.Collections.IList" />.</summary>
/// <param name="item">The object to remove from the <see cref="T:System.Collections.IList" />.</param>
/// <exception cref="T:System.ArgumentException">
/// <paramref name="item" /> is of a type that is not assignable to the <see cref="T:System.Collections.IList" />.</exception>
void IList.Remove (object item)
{
}
/// <summary>Copies the elements of the <see cref="T:System.Collections.Generic.List`1" /> to a new array.</summary>
/// <returns>An array containing copies of the elements of the <see cref="T:System.Collections.Generic.List`1" />.</returns>
public T[] ToArray ()
{
throw null;
}
/// <summary>Sets the capacity to the actual number of elements in the <see cref="T:System.Collections.Generic.List`1" />, if that number is less than a threshold value.</summary>
public void TrimExcess ()
{
}
/// <summary>Determines whether every element in the <see cref="T:System.Collections.Generic.List`1" /> matches the conditions defined by the specified predicate.</summary>
/// <param name="match">The <see cref="T:System.Predicate`1" /> delegate that defines the conditions to check against the elements.</param>
/// <exception cref="T:System.ArgumentNullException">
/// <paramref name="match" /> is <see langword="null" />.</exception>
/// <returns>
/// <see langword="true" /> if every element in the <see cref="T:System.Collections.Generic.List`1" /> matches the conditions defined by the specified predicate; otherwise, <see langword="false" />. If the list has no elements, the return value is <see langword="true" />.</returns>
public bool TrueForAll (Predicate<T> match)
{
throw null;
}
}
https://sharplab.io/#v2:CYLg1APgAgTAjAWAFBQAwAIpwCwG5nIB2Ahg...
https://www.fenet.jp/dotnet/column/language/1612/