Return type of Main() method in C#

Question

Why Main() method in C# can only return either a int value or void ?

Vulpes · Answer

Bearing in mind that the Main() method is the entry-point to the program when the Main() method returns then the program ends. Consequently only the operating system can consume any value returned by the Main() method. As this value (or Exit code) is always an integer there's not much point in the Main() method retuning anything but an int or void. If the return type is void then an exit code of 0 is returned unless there's an exception. By convention an exit code of 0 means that the program ran without error. In Windows the exit code is stored in the environment variable ERRORLEVEL and can be shown from the command line as follows: echo %ERRORLEVEL%