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Regex.Unescape Method

Updated: February 2009

Converts any escaped characters in the input string.

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

Public Shared Function Unescape ( _
	str As String _
) As String
Dim str As String 
Dim returnValue As String 

returnValue = Regex.Unescape(str)


Type: System.String

The input string containing the text to convert.

Return Value

Type: System.String
A string of characters with any escaped characters converted to their unescaped form.


str includes an unrecognized escape sequence.


str is Nothing.

The Unescape method performs one of the following two transformations:

  • It reverses the transformation performed by the Escape method by removing the escape character ("\") from each character escaped by the method. These include the \, *, +, ?, |, {, [, (,), ^, $,., #, and white space characters. In addition, the Unescape method unescapes the closing bracket (]) and closing brace (}) characters.


    Unescape cannot reverse an escaped string perfectly because it cannot deduce precisely which characters were escaped,

  • It replaces the representation of unprintable characters with the characters themselves. For example, it replaces \a with \x07. The character representations it replaces are \a, \b, \e, \n, \r, \f, \t, and \v.

If the Unescape method encounters other escape sequences that it cannot convert, such as \w or \s, it throws an ArgumentException.

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.

.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




February 2009

Added ArgumentException and expanded the Remarks section.

Content bug fix.