This documentation is archived and is not being maintained.

String.Trim Method

Removes all leading and trailing white-space characters from the current String object.

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

Public Function Trim As String

Return Value

Type: System.String
The string that remains after all white-space characters are removed from the start and end of the current string.

The Trim method removes from the current string all leading and trailing white-space characters. Each leading and trailing trim operation stops when a non-white-space character is encountered. For example, if the current string is "   abc   xyz   ", the Trim method returns "abc   xyz".


This method does not modify the value of the current instance. Instead, it returns a new string in which all leading and trailing white space characters found in the current instance are removed.

If the current string equals Empty or all the characters in the current instance consist of white-space characters, the method returns Empty.

White-space characters are defined by the Unicode standard. The Trim method removes any leading and trailing characters that produce a return value of true when they are passed to the Char.IsWhiteSpace method.

Notes to Callers

The .NET Framework 3.5 SP1 and earlier versions maintain an internal list of white-space characters that this method trims. Starting with the .NET Framework 4, the method trims all Unicode white-space characters (that is, characters that produce a true return value when they are passed to the Char.IsWhiteSpace method). Because of this change, the Trim method in the .NET Framework 3.5 SP1 and earlier versions removes two characters, ZERO WIDTH SPACE (U+200B) and ZERO WIDTH NO-BREAK SPACE (U+FEFF), that the Trim method in the .NET Framework 4 does not remove. In addition, the Trim method in the .NET Framework 3.5 SP1 and earlier versions does not trim three Unicode white-space characters: MONGOLIAN VOWEL SEPARATOR (U+180E), NARROW NO-BREAK SPACE (U+202F), and MEDIUM MATHEMATICAL SPACE (U+205F).

The following example uses the String.Trim method to remove any extra white space from strings entered by the user before concatenating them.

Module Example
   Public Sub Main()
      Console.Write("Enter your first name: ")
      Dim firstName As String = Console.ReadLine()

      Console.Write("Enter your middle name or initial: ")
      Dim middleName As String = Console.ReadLine()

      Console.Write("Enter your last name: ")
      Dim lastName As String = Console.ReadLine

      Console.WriteLine("You entered '{0}', '{1}', and '{2}'.", _
                        firstName, middleName, lastName)

      Dim name As String = ((firstName.Trim() + " " + middleName.Trim()).Trim() _
                           + " " + lastName.Trim()).Trim()                        
      Console.WriteLine("The result is " + name + ".")
   End Sub
End Module
' The following is possible output from this example:
'       Enter your first name:    John
'       Enter your middle name or initial:
'       Enter your last name:    Doe
'       You entered '   John  ', '', and '   Doe'.
'       The result is John Doe

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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