default switch statement not working

how come... my default in my switch statement doesn't execute if the user doesn't input anything?

Code:

void Menu()
{
     int answer;
     cout<<"\n<>Phone Book Entry Menu:";
     cout<<"\n  <1>Create New File";
     cout<<"\n  <2>Open File";
     cout<<"\n  <3>Write to File";
     cout<<"\n  <4>Delete File";
     cout<<"\n  <5>Quit";
     cout<<"\n  ->: ";
     cin>>answer;
     switch(answer)
     {
                   case 1:
                        MCreateFile();
                        break;
                   case 2:
                        cout<<"\nMOpenFile();"; // <+>MOpenFile();
                        break;
                   case 3:
                        cout<<"\nMWriteToFile();"; // <+>MWriteToFile();
                        break;
                   case 4:
                        cout<<"\nMDeleteFile();";  // <+>MDeleteFile
                        break;
                   case 5:
                        return;
                        break;
                   default:
                           cout<<"\nNot a valid entry!";
                           cout<<"\n  ->: ";
     }
}

Well the cin statement you have is pretty smart. If you kept pressing Enter or just put in a bunch of spaces, cin will wait until the user types something that has meaning.

o... right... the switch statement doesn't check if enter is being pressed...thats cin's job...
ok... how could i put cin<<answer; in a while loop...
ive already tried and failed...
something like

Code:

while(cin<<answer)
{
     cout<<"\n->: ";
}

cin uses the insertion operator >>. When you want to loop input, you must make an initial attempt to read something in, then if that fails, you can enter a while loop. Basically you want to:
- check the state of cin
- cin.clear(); reset all of cin's flags to make it okay for reuse
- ignore as many characters as you can
- try to get input again.
- lather, rinse, repeat