A reasonable misunderstanding for a person relatively new to javascript
(or coding).
The if/else conditional checks are NOT equivalent to a switch check.
Not.
Examine what the structure of a switch is:
switch(y)
you see, you passed already a variable, y.
As such, it is regarded as IMPLIED within all the case statements,
which IMPLICITLY compare it against the value passed to the case (so:
don't repeat 'y' within the case statements):
switch(y){
case 202:
break;
case 'dunno':
break;
}
that is, a switch statements gets in the variable y, and the CASE
statements gets in its possible or presumed VALUES ONLY.
As such, the limitation is that a switch statement isn't but an
if(y==something)
check in disguise.
The stress falls on the == operator.
A switch checks ONLY equivalences, NOT other type of comparisons: == is
IMPLIED.
You should consider it the same as passing arguments to a function,
with which perhaps you're already familiar:
function foo(arg){alert(arg)}
when you invoke that signature, the arg named variable is replaced with
its VALUES:
foo('hallo');
that obviously enough triggers al alert with written in it 'hallo'.
You do NOT repeat arg, in fact:
foo(arg='hallo');
that's wrong.
Please note that in some languages, like PHP, the SIGNATURE (NOT in the
invocation, that is) of a function can instead appear in that form,
which means assigning a DEFAULT:
function foo($arg='hallo'){print $arg;}
which means: this function has a DEFAULT value for the given argument
which is 'hallo' in case NO argument is passed upon invocation:
foo(); //prints the default 'hallo'
foo('hi'); //overrides the default, prints 'hi'
The SAME happens with the switch statement's logics.
I hope this brings in the sense of some coherence, and a lasting or
better insight in the whys of the issue that puzzles you.
If you wonder why it has not been arranged otherwise, I may concede a
switch plus plus allowing for more articulated comparisons say
switch(fantasy){
case (<1):
break;
case(>=2):
break;
}
might have been useful, but the fact is: we use if/else for the rest.
For mere == equivalences, we have the ALTERNATIVE of a switch
statement.
ps better if you put a semiciolon after the break
break;
makes things a bit more clear - stresses that a case ends that is.
Nothing more.
Alberto
http://www.unitedscripters.com/ 
