AS2 - Checking input box data problem

Hi, ive searched for answers to my problem for a while now but i just cant seem to find a quick and simple solution.

Here's my set up and problem;

I have 1 input box (instance name 'num5'),
1 button (with AS2 on it),

what i want to work;

when i enter '100' in the box (run some code)
when i enter more than 100 (run some different code)
when i don't enter anything (run different code again)

So far i have this actionscript on my button;

Code:

---

on (release){
        if (num5.text == "100"){
                trace("1");
        }
        else if (Number(num5) > 100){
                trace("2");
        }
        else if (num5 == null){
                trace("3");
        }       
}

---

the code within the if statements will be changed once i have this working, but for now trace is an easy way to test.

As you can see i have the first statement 'kind of' working, its cheating a bit but it works. Its the null and > 100 that i just dont know how to get working.

I've seen in some other places that i need to convert the string in the text box to a number or something along those lines, but really im quite lost, im not new to coding in general, but i know almost nothing about actionscript.

Can anyone help me out here? Thanks

AS2, Flash Player 7

Code:

---

on (release) {
        if (Number(num5.text) == 100) {
                trace("1");
        } else if (Number(num5.text)>100) {
                trace("2");
        } else if (isNaN(Number(num5.text))) {
                trace("3");
        } else {
                trace("4");
        }
}

---

Thanks a lot! That was exactly what i needed, wish i had come here first!