When do we use reference parameter?

You use a reference parameter whenever you want to be able to change the value of the parameter in the called method and at the same time change the value of the same parameter at the calling site where the method was called. Please refer to the following links for more information about reference parameters and parameter passing in C#:

http://ift.tt/1frwbh8

http://ift.tt/1oFpdLX