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StringConcat Method

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Concatenates the string representations of the elements in a specified Object array.

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

public static string Concat(
	params object[] args
static String^ Concat(
	... array<Object^>^ args
static member Concat : 
        [<ParamArrayAttribute>] args:Object[] -> string
Public Shared Function Concat (
	ParamArray args As Object()
) As String



An object array that contains the elements to concatenate.

Return Value


The concatenated string representations of the values of the elements in args.

Exception Condition

args is null.


Out of memory.

The method concatenates each object in args by calling the parameterless ToString method of that object; it does not add any delimiters.

StringEmpty is used in place of any null object in the array.

Notes to Callers:

This method is not called by C++ code. The C++ compiler resolves calls to Concat that have four or more object parameters as a call to Concat.

The following example demonstrates the use of the Concat method with an Object array.

using System;

public class ConcatTest {
    public static void Main() {
        // Create a group of objects.
        Test1 t1 = new Test1();
        Test2 t2 = new Test2();
        int i = 16;
        string s = "Demonstration";

        // Place the objects in an array.
        object [] o = { t1, i, t2, s };

        // Concatenate the objects together as a string. To do this,
        // the ToString method of each of the objects is called.

// Create two empty test classes.
class Test1 {

class Test2 {
// The example displays the following output:
//       Test116Test2Demonstration
Imports System

Public Class ConcatTest

    Public Shared Sub Main()
        Dim t1 As New Test1()
        Dim t2 As New Test2()
        Dim i As Integer = 16
        Dim s As String = "Demonstration"
        Dim o As Object() = {t1, i, t2, s}

        ' create a group of objects

        ' place the objects in an array

        ' concatenate the objects together as a string. To do this,
        ' the ToString method in the objects is called
    End Sub 'Main
End Class 'ConcatTest

' imagine these test classes are full-fledged objects...
Class Test1
End Class 'Test1

Class Test2
End Class 'Test2
Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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