Web Design in a Nutshell, 3rd Edition

switch

Now that you understand a few more control structures, it’s time to revisit the switch statement. As you saw in the previous switch example, each case within a switch is tried and, if it matches the argument of the switch, its statements are evaluated and the switch is exited (via break). There is also normally a default case (simply called default) that can act as a fallback (or an error alert) if none of the other cases are met.

To demonstrate the power of the switch, let’s spice up the countdown loop a bit:

    for( var i=10; i >=0; i-- ){
      switch( i ){
        case 2:
          alert( 'Almost...' );
          break;
        case 1:
          alert( 'There...' );
          break;
        case 0:
          alert( 'BOOM!' );
          break;
        default:
          alert( i );
          break;
      }
    }

This code would initiate a countdown from 10 to 0, alert-ing each number, but replacing 2 with Almost..., 1 with There..., and 0 with BOOM!.