Enumerable.Repeat<TResult>(TResult, Int32) 方法
定义
重要
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生成包含一个重复值的序列。
public:
generic <typename TResult>
static System::Collections::Generic::IEnumerable<TResult> ^ Repeat(TResult element, int count);public static System.Collections.Generic.IEnumerable<TResult> Repeat<TResult> (TResult element, int count);static member Repeat : 'Result * int -> seq<'Result>Public Function Repeat(Of TResult) (element As TResult, count As Integer) As IEnumerable(Of TResult)类型参数
- TResult
要在结果序列中重复的值的类型。
参数
- element
- TResult
要重复的值。
- count
- Int32
在生成序列中重复该值的次数。
返回
IEnumerable<TResult>
一个包含重复值的 IEnumerable<T>。
例外
count 小于 0。
示例
下面的代码示例演示如何使用 Repeat 生成重复值的序列。
IEnumerable<string> strings =
Enumerable.Repeat("I like programming.", 15);
foreach (String str in strings)
{
Console.WriteLine(str);
}
/*
This code produces the following output:
I like programming.
I like programming.
I like programming.
I like programming.
I like programming.
I like programming.
I like programming.
I like programming.
I like programming.
I like programming.
I like programming.
I like programming.
I like programming.
I like programming.
I like programming.
*/
' Repeat the same string to create a sequence.
Dim sentences As IEnumerable(Of String) =
Enumerable.Repeat("I like programming.", 15)
Dim output As New System.Text.StringBuilder
For Each sentence As String In sentences
output.AppendLine(sentence)
Next
' Display the output.
Console.WriteLine(output.ToString())
' This code produces the following output:
'
' I like programming.
' I like programming.
' I like programming.
' I like programming.
' I like programming.
' I like programming.
' I like programming.
' I like programming.
' I like programming.
' I like programming.
' I like programming.
' I like programming.
' I like programming.
' I like programming.
' I like programming.
注解
此方法通过使用延迟执行来实现。 即时返回值是一个对象，用于存储执行操作所需的所有信息。 在通过直接调用GetEnumerator其方法或通过在 C# For Each 或 foreach Visual Basic 中使用 来枚举对象之前，不会执行此方法表示的查询。
