Articolo
11/18/2011

String.Substring Method (Int32)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Retrieves a substring from this instance. The substring starts at a specified character position.

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

Syntax

'Declaration
Public Function Substring ( _
    startIndex As Integer _
) As String

public string Substring(
    int startIndex
)

Parameters

startIndex
Type: System.Int32
The zero-based starting character position of a substring in this instance.

Return Value

Type: System.String
A string that is equivalent to the substring that begins at startIndex in this instance, or Empty if startIndex is equal to the length of this instance.

Exceptions

Exception	Condition
ArgumentOutOfRangeException	startIndex is less than zero or greater than the length of this instance.

Remarks

The index is zero-based.

Note:
This method does not modify the value of the current instance. Instead, it returns a new string that begins at the startIndex position in the current string.

Examples

The following code example demonstrates obtaining a substring from a string.

Public Class Example

   Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      Dim info As String() = {"Name: Felica Walker", "Title: Mz.", "Age: 47", "Location: Paris", "Gender: F"}
      Dim found As Integer = 0

      outputBlock.Text &= "The initial values in the array are:" & vbCrLf
      Dim s As String
      For Each s In info
         outputBlock.Text &= s & vbCrLf

      Next s
      outputBlock.Text &= String.Format("{0}We want to retrieve only the key information. That is:", vbCrLf) & vbCrLf

      For Each s In info
         found = s.IndexOf(":")
         outputBlock.Text &= s.Substring((found + 1)).Trim() & vbCrLf
      Next s
   End Sub 'Main
End Class 'SubStringTest
' The example displays the following output:
'       The initial values in the array are:
'       Name: Felica Walker
'       Title: Mz.
'       Age: 47
'       Location: Paris
'       Gender: F
'       
'       We want to retrieve only the key information. That is:
'       Felica Walker
'       Mz.
'       47
'       Paris
'       F

using System;

public class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {

      string[] info = { "Name: Felica Walker", "Title: Mz.", "Age: 47", "Location: Paris", "Gender: F" };
      int found = 0;

      outputBlock.Text += "The initial values in the array are:" + "\n";
      foreach (string s in info)
         outputBlock.Text += s + "\n";

      outputBlock.Text += String.Format("{0}We want to retrieve only the key information. That is:", "\n") + "\n";

      foreach (string s in info)
      {
         found = s.IndexOf(":");
         outputBlock.Text += s.Substring(found + 1).Trim() + "\n";
      }
   }
}
// The example displays the following output:
//       The initial values in the array are:
//       Name: Felica Walker
//       Title: Mz.
//       Age: 47
//       Location: Paris
//       Gender: F
//       
//       We want to retrieve only the key information. That is:
//       Felica Walker
//       Mz.
//       47
//       Paris
//       F

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.

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