Find and replace text in a file in c#

The easiest way to find and replace text in a file is to use the Replace method of string as shown below.

string content= File.ReadAllText("FileName.txt");
text = content.Replace("find text", "replace text");
File.WriteAllText("FileName.txt", text);

You can use the Regex.Replace method for more complex replacements

Cheers,
Samitha