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String.Copy Method

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Creates a new instance of String with the same value as a specified String.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

Syntax

'Declaration
<SecuritySafeCriticalAttribute> _
Public Shared Function Copy ( _
    str As String _
) As String

[SecuritySafeCriticalAttribute]
public static string Copy(
    string str
)

Parameters

Return Value

Type: System.String
A new string with the same value as str.

Exceptions

Exception Condition
ArgumentNullException

str is nulla null reference (Nothing in Visual Basic).

Examples

The following code example displays two disimilar strings referenced by two variables, creates a copy of the first string, assigns a reference to the new string to the second variable, then displays the two strings referenced by the variables to demonstrate that the strings are now identical.

' Sample for String.Copy()

Class Example

   Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      Dim str1 As String = "abc"
      Dim str2 As String = "xyz"
      outputBlock.Text += String.Format("1) str1 = '{0}'", str1) & vbCrLf
      outputBlock.Text += String.Format("2) str2 = '{0}'", str2) & vbCrLf
      outputBlock.Text &= "Copy..." & vbCrLf
      str2 = [String].Copy(str1)
      outputBlock.Text += String.Format("3) str1 = '{0}'", str1) & vbCrLf
      outputBlock.Text += String.Format("4) str2 = '{0}'", str2) & vbCrLf
   End Sub 'Main
End Class 'Sample
'
'This example produces the following results:
'1) str1 = 'abc'
'2) str2 = 'xyz'
'Copy...
'3) str1 = 'abc'
'4) str2 = 'abc'
'

// Sample for String.Copy()
using System;

class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      string str1 = "abc";
      string str2 = "xyz";
      outputBlock.Text += String.Format("1) str1 = '{0}'", str1) + "\n";
      outputBlock.Text += String.Format("2) str2 = '{0}'", str2) + "\n";
      outputBlock.Text += "Copy..." + "\n";
      str2 = String.Copy(str1);
      outputBlock.Text += String.Format("3) str1 = '{0}'", str1) + "\n";
      outputBlock.Text += String.Format("4) str2 = '{0}'", str2) + "\n";
   }
}
/*
This example produces the following results:
1) str1 = 'abc'
2) str2 = 'xyz'
Copy...
3) str1 = 'abc'
4) str2 = 'abc'
*/

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.