Question

Can anyone help me?

This doesn’t seem to work:

switch (parseInt(charCode))
    {
        case (charCode >= 65 && charCode <=90): //UPPERCASE
            alert("UP");
        break;

        case (charCode >= 97 && charCode <=122): //LOWERCASE
            alert("LO");
        break;

        case (charCode >= 48 && charCode <=57): //NNUMBERS
            alert("NUM");
        break


    }

Thanks

Answer 1

[edit] Let’s add this disclaimer: this use of switch is considered EVIL or ABUSIVE. Some Disciples Of The Javascript also consider the use of ternaries as a major SIN. So beware of using them, because hell may await you, so the Gospel goes.

You can use switch like this ¹:

switch (true) {
   case (parseInt(charCode) >= 65 && parseInt(charCode) <=90): //UPPERCASE
       alert("UP");
       break;
   case (parseInt(charCode) >= 97 && parseInt(charCode) <=122): //LOWERCASE
       alert("LO");
       break;
   case (parseInt(charCode) >= 48 && parseInt(charCode) <=57): //NNUMBERS
       alert("NUM");
       break;
   default: break
}

it’s pretty bulky. You don’t have to use parseInt if you derive charCode came from event.keyCode. If you need to use parseInt, don’t forget to provide the radix, or better still, use Number to convert to a number.

Anyway using a ternary is an alternative for this:

alert( charCode >= 65 && charCode <= 90 
        ? 'UP'
        : charCode >= 97 && charCode <= 122
        ? 'LO'
        : charCode >= 48 && charCode <= 57 
        ? 'NUM'
        : 'OTHER'
);

[edit] Let’s see if the following alternative can satisfy the church of Javascript Coders…

Another alternative is using a RegExp with the character derived from the keyCode:

var chr      = String.fromCharCode(charCode),
    alertval =    /[a-z]/.test(chr) ?  'LO'
                : /[A-Z]/.test(chr) ?  'UP'
                : /[0-9]/.test(chr) ?  'NUM'
                : 'OTHER';
    alert(alertval);

As a last alternative (man, javascript is so versatile!) I present:

var check = String.fromCharCode(charCode)
             .replace(/([a-z])|([A-Z])|([0-9])|(.+)/,
                function(a,b,c,d) {
                  return b ? 'LO' : c ? 'UP' : d ? 'NUM' : 'OTH';
             });

¹ some notes on that ‘trick’