Basic Javascript WebDev help

Question

Hallo, I have to write a little java script and have no idea how and I thought that for a real JS Programmer it would be real easy to just tell me instead of me searching the web for hours.

Simple Problem:

I have some boxes with name TrackSelectPos_1 - TrackSelectPos_7. If one of those change I want to check if the value of the box is -1. If it is disable all the boxes with a higher number and set there value to -1. If the value is not -1 enable the box on the right (the box one higher).

So the basics things that I want to do are: 1. How to get the value 2. How do I disable/enable a box

Thanks for your help.

Answer 1

At the very basic level, assuming one of your textbox id is TextPOS_1

//1. Value  
var valueTB1 = document.getElementById('TextPOS_1');

alert (valueTB1 .value);
//2.To Disable
valueTB1.disabled = true;

You would need to wrap the above in a JavaScript Function...so that you can handle any number of textboxes.

Let me know if this helps and you need more clarification...

Answer 2

Assuming TrackSelectPos_1 is the id of your text box:

var box1 = document.getElementById('TrackSelectPos_1');
var box2 = document.getElementById('TrackSelectPos_2');

// This does it for only one text box.  You'd need to also perform the same for boxes 3 through 7.
if(box1.value == '-1'){
    box2.disabled = true;
} else {
    box2.disabled = false;
}