String.Replace Method (Char, Char)

This method performs an ordinal (case-sensitive and culture-insensitive) search to find oldChar.

Note
This method does not modify the value of the current instance. Instead, it returns a new string in which all occurrences of oldChar are replaced by newChar.

The following example creates a comma separated value list by substituting commas for the blanks between a series of numbers.

using System;

class stringReplace1 {
    public static void Main() {
        String str = "1 2 3 4 5 6 7 8 9";
        Console.WriteLine("Original string: \"{0}\"", str);
        Console.WriteLine("CSV string:      \"{0}\"", str.Replace(' ', ','));
    }
}
// 
// This example produces the following output: 
// Original string: "1 2 3 4 5 6 7 8 9" 
// CSV string:      "1,2,3,4,5,6,7,8,9" 
//

.NET Framework

.NET Framework Client Profile

Portable Class Library

.NET for Windows Store apps

Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Reference