Thread: Use of unassigned local variable 'i'

Originally Posted by C_ntua

I believe the only reasonable argument here, as shown in my example, is when the code forces the program to die with a function. The language can understand if you have a return statement, but has no idea what a function does.

But think that it would be kind of troublesome to "fix" the above. In my example, maybe Application.Exit() can fail and not terminate the program.

The real question here is this "Should it be a warning or an error?"

99% of the times, using unassigned variables in unacceptable. So what would you have done? Make it a simple warning?

I get the feeling of the question, been there myself, but always ask "what else could have been done?".

Actually, in your code above, the condition will still be evaluated. Application.Exit() does NOT immediately and unconditionally kill the program. Rather, it puts a message in the message pump that requests a shutdown. The remainder of the function will continue to execute (assuming that it's executing on the same thread as the message pump) since the message can't be processed until the currently executing function returns. Only when the message pump next checks for messages will the program shut down.

Example: The following DOES write the line of text to the log:

Code:

            StreamWriter loggingFile = new StreamWriter(@"outputLog.txt");
            
            /* ...  */

            Application.Exit();
            loggingFile.WriteLine("Exit has been called");
            loggingFile.Close();

You probably could do a scorched-earth method like get a handle to the current process and kill it, but that's CERTAINLY not good practice.