How to populate and use an array in Javascript?

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Aug 9th, 2004, 11:30 AM
softwareguy74

How to populate and use an array in Javascript?

I need to create an array in Javascript in my web page that contains 3 columns:

CategoryID
ReasonID
Value

So for example, I need an array to have the following info:

1,1,Value1
1,2,Value2
1,3,Value3
2,1,Value1
2,2,Value2
2,3,Value3

I will then have 2 comboboxes on my web page. The first combobox will simply contain a CategoryID value. The second combobox needs to be populated based on which CategoryID is selected in combobox 1. So for example, if CategoryID 2 is selected in combobox 1, I need combobox 2 to populated with all values from the array that contain a 2 as the first element.

An example of how to do this would be greatly appreciated.
Aug 9th, 2004, 11:58 AM
riis

I'd use objects for this

Code:

// First declare the object type, can be done with a function function ObjectName(categoryID, reasonID, value) { this.categoryID = categoryID; this.reasonID = reasonID; this.value = value; } // Then declare the array var myArray = new Array(); // Make an event handler which fills the combo boxes, place it in the body tag, like: <body onload="init()"> function init() { // Fill the array myArray.push( new ObjectName(1, 1, "Value1"), new ObjectName(1, 2, "Value2"), ... new ObjectName(2, 3, "Value3")); // Loop through the array and fill the combobox var myCombo = document.getElementById("comboId")'; for(var i = 0; i < myArray.length; i++) { myCombo.add(new Option(myArray[i].categoryID, myArray[i].categoryID, false, false); } return; }

I hope you can do the rest from here, like filling the second combo box when the user selects a value from the first. If not just put your questions here.
You might read a bit about event handling in JavaScript. You can put an event on a select box the same way as I did on the body tag. Use the onclick event for this purpose.
Aug 9th, 2004, 04:55 PM
softwareguy74

Seems to be erroring out on the following line:

myCombo.add(new Option(myArray[i].categoryID, myArray[i].categoryID, false, false);

Any ideas?
Aug 9th, 2004, 05:18 PM
softwareguy74

Nevermind, I see that a parenthesis was missing at the end...
Aug 10th, 2004, 02:30 AM
riis

Quote:

Originally posted by dbassettt74
Nevermind, I see that a parenthesis was missing at the end...

Yup, my mistake, didn't test it