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String.Contains Method

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

Returns a value indicating whether the specified String object occurs within this string.

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

Syntax

'Declaration
Public Function Contains ( _
    value As String _
) As Boolean
public bool Contains(
    string value
)

Parameters

Return Value

Type: System.Boolean
true if the value parameter occurs within this string, or if value is the empty string (""); otherwise, false.

Exceptions

Exception Condition
ArgumentNullException

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

Remarks

This method performs an ordinal (case-sensitive and culture-insensitive) comparison. The search begins at the first character position of this string and continues through the last character position.

Examples

The following code example determines whether the string "fox" is a substring of a familiar quotation.

' This example demonstrates the String.Contains() method

Class Example
   Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      Dim s1 As String = "The quick brown fox jumps over the lazy dog"
      Dim s2 As String = "fox"
      Dim b As Boolean
      b = s1.Contains(s2)
      outputBlock.Text += String.Format("Is the string, s2, in the string, s1?: {0}", b) & vbCrLf
   End Sub 'Main
End Class 'Sample
'
'This example produces the following results:
'
'Is the string, s2, in the string, s1?: True
'
// This example demonstrates the String.Contains() method
using System;

class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      string s1 = "The quick brown fox jumps over the lazy dog";
      string s2 = "fox";
      bool b;
      b = s1.Contains(s2);
      outputBlock.Text += String.Format("Is the string, s2, in the string, s1?: {0}", b) + "\n";
   }
}
/*
This example produces the following results:

Is the string, s2, in the string, s1?: True
*/

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.