You can get the answer yourself by writing few lines of code. Isn't it the beauty of programming that you get the result immmediatly?
Anyways, try this:
string input = "***Lets try to understand Replace function.*** Should not be that diffcult ?";
Console.WriteLine(input);
Console.WriteLine(input.Replace("*", "%"));
Console.WriteLine(input.Replace("?", "_%"));
I hope you get the answer yourself. Trust me, it gives a great feeling. :)
Read more about it here:
http://www.dotnetperls.com/replace[
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http://msdn.microsoft.com/en-us/library/fk49wtc1.aspx[
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