This documentation is archived and is not being maintained.

String.Join Method (String, String())

Updated: January 2011

Concatenates a specified separator String between each element of a specified String array, yielding a single concatenated string.

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

Public Shared Function Join ( _
	separator As String, _
	value As String() _
) As String
Dim separator As String 
Dim value As String()
Dim returnValue As String 

returnValue = String.Join(separator, _


Type: System.String

A String.

Type: System.String()

An array of String.

Return Value

Type: System.String
A String consisting of the elements of value interspersed with the separator string.


value is Nothing.

For example if separator is ", " and the elements of value are "apple", "orange", "grape", and "pear", Join(separator, value) returns "apple, orange, grape, pear".

If separator is Nothing, an empty string is used instead. If any element in value is Nothing, an empty string is used instead.

The following example demonstrates the Join method.

Imports System

Public Class JoinTest

    Public Shared Sub Main()

        Console.WriteLine(MakeLine(0, 5, ", "))
        Console.WriteLine(MakeLine(1, 6, "  "))
        Console.WriteLine(MakeLine(9, 9, ": "))
        Console.WriteLine(MakeLine(4, 7, "< "))
    End Sub 'Main

    Private Shared Function MakeLine(initVal As Integer, multVal As Integer, sep As String) As String 
        Dim sArr(10) As String 
        Dim i As Integer 

        For i = initVal To (initVal + 10) - 1
            sArr((i - initVal)) = [String].Format("{0,-3}", i * multVal)

        Next i
        Return [String].Join(sep, sArr)
    End Function 'MakeLine
End Class 'JoinTest

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




January 2011

Noted that an empty string is substituted for any null element in the array.

Customer feedback.