Enumerable.Repeat<TResult>(TResult, Int32) 方法
重要
部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。
產生包含一個重複值的序列。
public:
generic <typename TResult>
static System::Collections::Generic::IEnumerable<TResult> ^ Repeat(TResult element, int count);C#
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)- TResult
要在結果序列中重複出現的值之類型。
- element
- TResult
要重複的值。
- count
- Int32
這個值要在產生的序列中重複出現的次數。
IEnumerable<TResult>
包含重複值的 IEnumerable<T>。
count 小於 0。
下列程式代碼範例示範如何使用 Repeat 來產生重複值的序列。
C#
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.
此方法是使用延後執行來實作。 立即傳回值是物件，可儲存執行動作所需的所有資訊。 除非直接在 GetEnumerator C# 或 Visual Basic 中使用 foreach 來列舉對象，否則 For Each 不會執行這個方法所表示的查詢。
| 產品 | 版本 |
|---|---|
| .NET | Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9 |
| .NET Framework | 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
| .NET Standard | 1.0, 1.1, 1.2, 1.3, 1.4, 1.6, 2.0, 2.1 |
| UWP | 10.0 |
