How to Get Old String After Replce String in Regex in C#

Question

Hello,

 

string str = "Computer & Web Solution / deva/sasasa@ww";

 String stre = Regex.Replace(str, @"[^0-9a-zA-Z]+", "-");

 

My Result = Computer-Web-Solution-deva-sasasa-ww 

How to get   "Computer & Web Solution / deva/sasasa@ww" (Old String )  with Regex Or other Code