Enumerable.Append<TSource>(IEnumerable<TSource>, TSource) 方法

定义

命名空间:

System.Linq

程序集:

System.Linq.dll

Source:

AppendPrepend.cs

将一个值追加到序列末尾。

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static System::Collections::Generic::IEnumerable<TSource> ^ Append(System::Collections::Generic::IEnumerable<TSource> ^ source, TSource element);

public static System.Collections.Generic.IEnumerable<TSource> Append<TSource> (this System.Collections.Generic.IEnumerable<TSource> source, TSource element);

static member Append : seq<'Source> * 'Source -> seq<'Source>

<Extension()>
Public Function Append(Of TSource) (source As IEnumerable(Of TSource), element As TSource) As IEnumerable(Of TSource)

类型参数

TSource

source 的元素类型。

参数

source

IEnumerable<TSource>

值序列。

element

TSource

要追加到 source 的值。

返回

IEnumerable<TSource>

以 element 结尾的新序列。

例外

ArgumentNullException

source 为 null。

示例

下面的代码示例演示如何使用 Append 将值追加到序列的末尾。

// Creating a list of numbers
List<int> numbers = new List<int> { 1, 2, 3, 4 };

// Trying to append any value of the same type
numbers.Append(5);

// It doesn't work because the original list has not been changed
Console.WriteLine(string.Join(", ", numbers));

// It works now because we are using a changed copy of the original list
Console.WriteLine(string.Join(", ", numbers.Append(5)));

// If you prefer, you can create a new list explicitly
List<int> newNumbers = numbers.Append(5).ToList();

// And then write to the console output
Console.WriteLine(string.Join(", ", newNumbers));

// This code produces the following output:
//
// 1, 2, 3, 4
// 1, 2, 3, 4, 5
// 1, 2, 3, 4, 5

' Creating a list of numbers
Dim numbers As New List(Of Integer)(New Integer() {1, 2, 3, 4})

' Trying to append any value of the same type
numbers.Append(5)

' It doesn't work because the original list has not been changed
Console.WriteLine(String.Join(", ", numbers))

' It works now because we are using a changed copy of the original list
Console.WriteLine(String.Join(", ", numbers.Append(5)))

' If you prefer, you can create a new list explicitly
Dim newNumbers As List(Of Integer) = numbers.Append(5).ToList

' And then write to the console output
Console.WriteLine(String.Join(", ", newNumbers))

' This code produces the following output:
'
' 1, 2, 3, 4
' 1, 2, 3, 4, 5
' 1, 2, 3, 4, 5

注解

注意

此方法不会修改集合的元素。 而是使用新元素创建集合的副本。