this.FORM1 isn't going to work because "this" = the element that triggered
the event = the other select control, which does not have FORM1 as a
property.

You want to say "document.FORM1".

-Roy

-----Original Message-----
From: Femy Praseeth [mailto:fpraseet@s...]
Sent: Friday, October 25, 2002 7:24 PM
To: javascript
Subject: [javascript] Javascript to add items to listbox based on
selection in another listbox


Hi all

I am new to this list and new to Javascript. I would appreciate any help
from the experts on this proble I have.  have two listboxes in my form (1)
Brd_Name and (2)Brd_Type. My aim is when the user selects a Brd_Name from
the listbox, populate the Brd_Type with corresponding Brd Type values.

For eg: For Brd_Name: ATU, Brd_Types: ATU_32G, ATU_32T
For Brd_Name:MCU, Brd_Types:MCU_CS, MCU_MS
Etc

In the onchange event of Brd_Name I wrote the following code

===============CODE=============
function Brd_Name_onchange() {
    var brdName;
    brdName = this.FORM1.Brd_Name
[this.FORM1.Brd_Name.selectedIndex].value; //Get the value selected in Brd
Name

    if (brdName == "ATU"){
         clearList(this.FORM1.Brd_Type);
            this.FORM1.Brd_Type.Options[0] = new Option
("ATU_32G","ATU_32G");
         this.FORM1.Brd_Type.options[1] = new Option("ATU_32T","ATU_32T");
    }
    else if (brdName == "MCU"){
         clearList(this.FORM1.Brd_Type);
            this.FORM1.Brd_Type.Options[0] = new Option("MCU_CS","MCU_CS");
         this.FORM1.Brd_Type.options[1] = new Option("MCU_MS","MCU_MS");
    }


    this.FORM1.Brd_Type.Options[0].selected=true;

return true;

}

function clearList(ctrl){
    // This function clears out the contents of a list box
    for (var i = ctrl.options.length; i >=0; i--){
         ctrl.options[i] = null;
    }
    ctrl.selectedIndex = -1;
}
=========CODE======

Now everytime I run this code I get the
error "this.FORM1.Brd_Type.options' is null or not an object

Can someone pls tell me where I am making the mistake..Is it not possible
to do this.

Any help is appreciated..I have already spend a lot of time on this and am
kinda desperate for an answer

TIA

---

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