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c# - Why do you need to put break after the last label of a switch statement?

Surely the compiler knows that it's the last label of the switch statement?

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It's because in C++ this is what happens:

switch(a)
{
     case 1:
        // do stuff

     case 2:
        // do other stuff
}

If a is 1, then - according to C++ rules - both "do stuff" and "do other stuff" would happen. So that C++ programmers coming to C# do not get tripped up (and to make code clearer all 'round), C# requires that you explicitly specify whether you want to break or fall through to a different label.

Now, as for why you need the break on the last block, that's a simple matter of consistency. It also make re factoring easier: if you move the cases around, you don't suddenly end up with errors because of a missing break statement. Also, what happens when you want to add another label, etc, etc.


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