Auto Fill form to be filled in 10seconds.

Hi I need a software or something which will allow us to auto fill forms. Note this is not just some simple auto fill. Only bid if you know how to get this done in a very professional manner. The forms stays the same the only changes are the codes from the back for field identification like for city it used to say field rule "(?:^ctl00\$ContentPlaceHolder1\$txtCy121854$)" now they changed to "(?:^ctl00\$ContentPlaceHolder1\$txtCity$)" but in the text and layout is still name says city. The same thing happens in the full form like name, surname etc. We need something that can fill the form in few seconds. Anymore questions please ask.