StringBuilder.Replace Method (Char, Char, Int32, Int32)
Microsoft Silverlight will reach end of support after October 2021. Learn more.
Replaces, within a substring of this instance, all occurrences of a specified character with another specified character.
Namespace: System.Text
Assembly: mscorlib (in mscorlib.dll)
Syntax
'Declaration
Public Function Replace ( _
oldChar As Char, _
newChar As Char, _
startIndex As Integer, _
count As Integer _
) As StringBuilder
public StringBuilder Replace(
char oldChar,
char newChar,
int startIndex,
int count
)
Parameters
- oldChar
Type: System.Char
The character to replace.
- newChar
Type: System.Char
The character that replaces oldChar.
- startIndex
Type: System.Int32
The position in this instance where the substring begins.
- count
Type: System.Int32
The length of the substring.
Return Value
Type: System.Text.StringBuilder
A reference to this instance with oldChar replaced by newChar in the range from startIndex to startIndex + count -1.
Exceptions
| Exception | Condition |
|---|---|
| ArgumentOutOfRangeException | startIndex + count is greater than the length of the value of this instance. -or- startIndex or count is less than zero. |
Remarks
The size of the StringBuilder is unchanged because characters are only replaced. This method is case-sensitive.
Examples
The following code example demonstrates the Replace method.
Imports System.Text
Class Example
Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
' 0----+----1----+----2----+----3----+----4---
' 01234567890123456789012345678901234567890123
Dim str As String = "The quick br!wn d#g jumps #ver the lazy cat."
Dim sb As New StringBuilder(str)
outputBlock.Text &= vbCrLf
outputBlock.Text &= "StringBuilder.Replace method" & vbCrLf
outputBlock.Text &= vbCrLf
outputBlock.Text &= "Original value:" & vbCrLf
Show(outputBlock, sb)
sb.Replace("#"c, "!"c, 15, 29) ' Some '#' -> '!'
Show(outputBlock, sb)
sb.Replace("!"c, "o"c) ' All '!' -> 'o'
Show(outputBlock, sb)
sb.Replace("cat", "dog") ' All "cat" -> "dog"
Show(outputBlock, sb)
sb.Replace("dog", "fox", 15, 20) ' Some "dog" -> "fox"
outputBlock.Text &= "Final value:" & vbCrLf
Show(outputBlock, sb)
End Sub 'Main
Public Shared Sub Show(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal sbs As StringBuilder)
Dim rule1 As String = "0----+----1----+----2----+----3----+----4---"
Dim rule2 As String = "01234567890123456789012345678901234567890123"
outputBlock.Text &= rule1 & vbCrLf
outputBlock.Text &= rule2 & vbCrLf
outputBlock.Text += String.Format("{0}", sbs.ToString()) & vbCrLf
outputBlock.Text &= vbCrLf
End Sub 'Show
End Class 'Sample
'
'This example produces the following results:
'
'StringBuilder.Replace method
'
'Original value:
'0----+----1----+----2----+----3----+----4---
'01234567890123456789012345678901234567890123
'The quick br!wn d#g jumps #ver the lazy cat.
'
'0----+----1----+----2----+----3----+----4---
'01234567890123456789012345678901234567890123
'The quick br!wn d!g jumps !ver the lazy cat.
'
'0----+----1----+----2----+----3----+----4---
'01234567890123456789012345678901234567890123
'The quick brown dog jumps over the lazy cat.
'
'0----+----1----+----2----+----3----+----4---
'01234567890123456789012345678901234567890123
'The quick brown dog jumps over the lazy dog.
'
'Final value:
'0----+----1----+----2----+----3----+----4---
'01234567890123456789012345678901234567890123
'The quick brown fox jumps over the lazy dog.
'
using System;
using System.Text;
class Example
{
public static void Demo(System.Windows.Controls.TextBlock outputBlock)
{
// 0----+----1----+----2----+----3----+----4---
// 01234567890123456789012345678901234567890123
string str = "The quick br!wn d#g jumps #ver the lazy cat.";
StringBuilder sb = new StringBuilder(str);
outputBlock.Text += "\n";
outputBlock.Text += "StringBuilder.Replace method" + "\n";
outputBlock.Text += "\n";
outputBlock.Text += "Original value:" + "\n";
Show(outputBlock, sb);
sb.Replace('#', '!', 15, 29); // Some '#' -> '!'
Show(outputBlock, sb);
sb.Replace('!', 'o'); // All '!' -> 'o'
Show(outputBlock, sb);
sb.Replace("cat", "dog"); // All "cat" -> "dog"
Show(outputBlock, sb);
sb.Replace("dog", "fox", 15, 20); // Some "dog" -> "fox"
outputBlock.Text += "Final value:" + "\n";
Show(outputBlock, sb);
}
public static void Show(System.Windows.Controls.TextBlock outputBlock, StringBuilder sbs)
{
string rule1 = "0----+----1----+----2----+----3----+----4---";
string rule2 = "01234567890123456789012345678901234567890123";
outputBlock.Text += rule1 + "\n";
outputBlock.Text += rule2 + "\n";
outputBlock.Text += String.Format("{0}", sbs.ToString()) + "\n";
outputBlock.Text += "\n";
}
}
/*
This example produces the following results:
StringBuilder.Replace method
Original value:
0----+----1----+----2----+----3----+----4---
01234567890123456789012345678901234567890123
The quick br!wn d#g jumps #ver the lazy cat.
0----+----1----+----2----+----3----+----4---
01234567890123456789012345678901234567890123
The quick br!wn d!g jumps !ver the lazy cat.
0----+----1----+----2----+----3----+----4---
01234567890123456789012345678901234567890123
The quick brown dog jumps over the lazy cat.
0----+----1----+----2----+----3----+----4---
01234567890123456789012345678901234567890123
The quick brown dog jumps over the lazy dog.
Final value:
0----+----1----+----2----+----3----+----4---
01234567890123456789012345678901234567890123
The quick brown fox jumps over the lazy dog.
*/
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.