Regex.Replace Method (String, String) (System.Text.RegularExpressions)

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Replace Method (String, String)

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This page is specific to

Microsoft Visual Studio 2008/.NET Framework 3.5

Other versions are also available for the following:

.NET Framework Class Library

Regex..::.Replace Method (String, String)

Within a specified input string, replaces all strings that match a regular expression pattern with a specified replacement string.

Namespace: System.Text.RegularExpressions
Assembly: System (in System.dll)

Syntax

Visual Basic (Declaration)

Public Function Replace ( _
    input As String, _
    replacement As String _
) As String

Visual Basic (Usage)

Dim instance As Regex
Dim input As String
Dim replacement As String
Dim returnValue As String

returnValue = instance.Replace(input, _
    replacement)

public string Replace(
    string input,
    string replacement
)

Visual C++

public:
String^ Replace(
    String^ input, 
    String^ replacement
)

JScript

public function Replace(
    input : String, 
    replacement : String
) : String

Parameters

input: Type: System..::.String
The string to search for a match.

replacement: Type: System..::.String
The replacement string.

Return Value

Type: System..::.String
A new string that is identical to the input string, except that a replacement string takes the place of each matched string.

Exceptions

Exception	Condition
ArgumentNullException	input is nullNothingnullptra null reference (Nothing in Visual Basic). -or- replacement is nullNothingnullptra null reference (Nothing in Visual Basic).

Exception

Condition

ArgumentNullException

input is nullNothingnullptra null reference (Nothing in Visual Basic).

-or-

replacement is nullNothingnullptra null reference (Nothing in Visual Basic).

Remarks

The search for matches starts at the beginning of the input parameter string. The regular expression is the pattern defined by the constructor for the current Regex object.

Examples

The following code example demonstrates the Regex..::.Replace method.

Visual Basic

' This code example demonstrates the System.Text.Regular-
' Expressions.Regex.Replace(String, String) method.

Imports System
Imports System.Text.RegularExpressions

Class Sample
    Public Shared Sub Main() 
        ' Create a regular expression that matches a series of one 
        ' or more white spaces.
        Dim pattern As String = "\s+"
        Dim rgx As New Regex(pattern)

        ' Declare a string consisting of text and white spaces.
        Dim inputStr As String = "a   b   c   d"

        ' Replace runs of white space in the input string with a
        ' comma and a blank.
        Dim outputStr As String = rgx.Replace(inputStr, ", ")

        ' Display the resulting string.
        Console.WriteLine("Pattern:       ""{0}""", pattern)
        Console.WriteLine("Input string:  ""{0}""", inputStr)
        Console.WriteLine("Output string: ""{0}""", outputStr)
    End Sub 'Main
End Class 'Sample

'
'This code example produces the following results:
'
'Pattern:       "\s+"
'Input string:  "a   b   c   d"
'Output string: "a, b, c, d"
'

// This code example demonstrates the System.Text.Regular-
// Expressions.Regex.Replace(String, String) method.

using System;
using System.Text.RegularExpressions;

class Sample 
{
    public static void Main() 
    {
// Create a regular expression that matches a series of one 
// or more white spaces.
    string pattern = @"\s+";
    Regex rgx = new Regex(pattern);

// Declare a string consisting of text and white spaces.
    string inputStr = "a   b   c   d";

// Replace runs of white space in the input string with a
// comma and a blank.
    string outputStr = rgx.Replace(inputStr, ", ");

// Display the resulting string.
    Console.WriteLine("Pattern:       \"{0}\"", pattern);
    Console.WriteLine("Input string:  \"{0}\"", inputStr);
    Console.WriteLine("Output string: \"{0}\"", outputStr);
    }
}
/*
This code example produces the following results:

Pattern:       "\s+"
Input string:  "a   b   c   d"
Output string: "a, b, c, d"

*/

Platforms

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Version Information

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0

Reference

Regex Class

Regex Members

Replace Overload

System.Text.RegularExpressions Namespace

Other Resources

Substitutions