Throwing ArgumentNullException

Question

Suppose I have a method that takes an object of some kind as an argument. Now say that if this method is passed a null argument, it\'s a fatal error and an exception shoul

Answer 1

You should explicitly throw an ArgumentNullException if you are expecting the input to not be null. You might want to write a class called Guard that provides helper methods for this. So your code will be:

void someMethod(SomeClass x, SomeClass y)
{
    Guard.NotNull(x,"x","someMethod received a null x argument!");
    Guard.NotNull(y,"y","someMethod received a null y argument!");


    x.doSomething();
    y.doSomething();
}

The NonNull method would do the nullity check and throw a NullArgumentException with the error message specified in the call.