MACROMEDIA FLASH 8-LEARNING ACTIONSCRIPT 2.0 IN FLASH Manual page 771

You can write
switch
switch (condition) {
case A :
// statements
// falls through
case B :
// statements
break;
case Z :
// statements
break;
default :
// statements
break;
}
Writing try..catch and try..catch..finally statements
Write and
try..catch
var myErr:Error;
// try..catch
try {
// statements
} catch (myErr) {
// statements
}
// try..catch..finally
try {
// statements
} catch (myErr) {
// statements
} finally {
// statements
}
statements using the following format:
try..catch..finally
statements using the following formats:
Formatting ActionScript syntax 771