Статья
11/18/2011

Enumerable.Repeat<TResult> Method

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Generates a sequence that contains one repeated value.

Namespace: System.Linq
Assembly: System.Core (in System.Core.dll)

Syntax

'Declaration
Public Shared Function Repeat(Of TResult) ( _
    element As TResult, _
    count As Integer _
) As IEnumerable(Of TResult)

public static IEnumerable<TResult> Repeat<TResult>(
    TResult element,
    int count
)

Type Parameters

TResult
The type of the value to be repeated in the result sequence.

Parameters

element
Type: TResult
The value to be repeated.

count
Type: System.Int32
The number of times to repeat the value in the generated sequence.

Return Value

Type: System.Collections.Generic.IEnumerable<TResult>
An IEnumerable<T> that contains a repeated value.

Exceptions

Exception	Condition
ArgumentOutOfRangeException	count is less than 0.

Remarks

This method is implemented by using deferred execution. The immediate return value is an object that stores all the information that is required to perform the action. The query represented by this method is not executed until the object is enumerated either by calling its GetEnumerator method directly or by using foreach in Visual C# or For Each in Visual Basic.

Examples

The following code example demonstrates how to use Repeat<TResult> to generate a sequence of a repeated value.

      ' 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.
      outputBlock.Text &= output.ToString() & vbCrLf

      ' 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.

      IEnumerable<string> strings =
          Enumerable.Repeat("I like programming.", 15);

      foreach (String str in strings)
      {
         outputBlock.Text += str + "\n";
      }

      /*
       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.
      */

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

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