Should I Throw ArgumentNullException if a string is blank?

Question

I working on a method that does something given a string parameter. A valid value for the string parameter is anything other than null or string.Empty. So my code looks li

Answer 1

This depends on circumstance really.

The question comes down to, is it really an error? By that I mean do you always expect a value? If you do, then probably your best bet here is creating your own Exception, perhaps like so:

class StringEmptyOrNullException : Exception
{
}

Where you can also add your own constructors and added information etc.

If it however is not an "exceptional" happening in your program, if would probably be a better idea to return null from the method and handle it from there. Just remember, Exception's are for exceptional conditions.

Hope this helps,

Kyle