StringBuilder.Replace Method (String, String, Int32, Int32)


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Replaces, within a substring of this instance, all occurrences of a specified string with another specified string.

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

member Replace : 
        oldValue:string *
        newValue:string *
        startIndex:int *
        count:int -> StringBuilder


Type: System.String

The string to replace.

Type: System.String

The string that replaces oldValue, or null.

Type: System.Int32

The position in this instance where the substring begins.

Type: System.Int32

The length of the substring.

Return Value

Type: System.Text.StringBuilder

A reference to this instance with all instances of oldValue replaced by newValue in the range from startIndex to startIndex + count - 1.

Exception Condition

oldValue is null.


The length of oldValue is zero.


startIndex or count is less than zero.


startIndex plus count indicates a character position not within this instance.


Enlarging the value of this instance would exceed MaxCapacity.

This method performs an ordinal, case-sensitive comparison to identify occurrences of oldValue in the specified substring. If newValue is nullorString.Empty, all occurrences of oldValue are removed.

The following example demonstrates the Replace method.

No code example is currently available or this language may not be supported.

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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