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String.Concat Method (String, String, String)

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Concatenates three specified instances of String.

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

Syntax

'Declaration
<SecuritySafeCriticalAttribute> _
Public Shared Function Concat ( _
    str0 As String, _
    str1 As String, _
    str2 As String _
) As String
[SecuritySafeCriticalAttribute]
public static string Concat(
    string str0,
    string str1,
    string str2
)

Parameters

Return Value

Type: System.String
The concatenation of str0, str1, and str2.

Remarks

The method concatenates str0, str1, and str2; it does not add any delimiters.

An Empty string is used in place of any null argument.

Examples

The following example illustrates the Concat(Object) method.

Option Explicit On
Option Strict On

Imports System.Globalization

Public Class Example

   Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      Dim dt As DateTime = DateTime.Now
      Dim myformat() As String = {"d", "D", _
                                  "f", "F", _
                                  "g", "G", _
                                  "m", _
                                  "r", _
                                  "s", _
                                  "t", "T", _
                                  "u", "U", _
                                  "y", _
                                  "dddd, MMMM dd yyyy", _
                                  "ddd, MMM d ""'""yy", _
                                  "dddd, MMMM dd", _
                                  "M/yy", _
                                  "dd-MM-yy"}
      Dim mydate As String
      Dim i As Integer
      For i = 0 To myformat.Length - 1
         mydate = dt.ToString(myformat(i), DateTimeFormatInfo.InvariantInfo)
         outputBlock.Text += String.Format(String.Concat(myformat(i), " :", mydate)) & vbCrLf
      Next i

      ' Output.
      '
      ' d :08/17/2000
      ' D :Thursday, August 17, 2000
      ' f :Thursday, August 17, 2000 16:32
      ' F :Thursday, August 17, 2000 16:32:32
      ' g :08/17/2000 16:32
      ' G :08/17/2000 16:32:32
      ' m :August 17
      ' r :Thu, 17 Aug 2000 23:32:32 GMT
      ' s :2000-08-17T16:32:32
      ' t :16:32
      ' T :16:32:32
      ' u :2000-08-17 23:32:32Z
      ' U :Thursday, August 17, 2000 23:32:32
      ' y :August, 2000
      ' dddd, MMMM dd yyyy :Thursday, August 17 2000
      ' ddd, MMM d "'"yy :Thu, Aug 17 '00
      ' dddd, MMMM dd :Thursday, August 17
      ' M/yy :8/00
      ' dd-MM-yy :17-08-00
   End Sub 'Main 
End Class 'MainClass
using System;
using System.Globalization;

public class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      DateTime dt = DateTime.Now;
      String[] format = {
            "d", "D",
            "f", "F",
            "g", "G",
            "m",
            "r",
            "s",
            "t", "T",
            "u", "U",
            "y",
            "dddd, MMMM dd yyyy",
            "ddd, MMM d \"'\"yy",
            "dddd, MMMM dd",
            "M/yy",
            "dd-MM-yy",
        };
      String date;
      for (int i = 0; i < format.Length; i++)
      {
         date = dt.ToString(format[i], DateTimeFormatInfo.InvariantInfo);
         outputBlock.Text += String.Format(String.Concat(format[i], " :", date)) + "\n";
      }

      /** Output.
       * d :08/17/2000
       * D :Thursday, August 17, 2000
       * f :Thursday, August 17, 2000 16:32
       * F :Thursday, August 17, 2000 16:32:32
       * g :08/17/2000 16:32
       * G :08/17/2000 16:32:32
       * m :August 17
       * r :Thu, 17 Aug 2000 23:32:32 GMT
       * s :2000-08-17T16:32:32
       * t :16:32
       * T :16:32:32
       * u :2000-08-17 23:32:32Z
       * U :Thursday, August 17, 2000 23:32:32
       * y :August, 2000
       * dddd, MMMM dd yyyy :Thursday, August 17 2000
       * ddd, MMM d "'"yy :Thu, Aug 17 '00
       * dddd, MMMM dd :Thursday, August 17
       * M/yy :8/00
       * dd-MM-yy :17-08-00
       */
   }
}

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.