Can't get value of select box in IE or Chrome?

Question

I've been building my site in FF and just realized that it's not working in IE or Chrome (the Javascript, that is). Using IE's JS debugger I found that it is spitting out the following error:

SCRIPT5007: Unable to get value of the property 'value': object is null or undefined ...

For the following code:

var myvar = document.getElementById("selectboxid").value;

It works fine in FF, but not in IE or Chrome.

The HTML for the select box looks like this:

<select name="selectboxid" id="selectboxid" size="1" autocomplete="off" tabindex="5" >
<option value="1">One</option>
<option value="2">Two</option>
...

Am I doing something wrong? If so, why does it work fine in FF?

Thanks for your help.

try it like this - http://stackoverflow.com/q/1085801/1499781 — Zoltan Toth, Oct 25 '12 at 00:25
@KevinBoucher - maybe.. I just tried it and I'm getting an error. See my comment below. — Nate, Oct 25 '12 at 00:30

Jeff Robert Dagala · Accepted Answer · 2012-10-25T00:59:28.160

4

you could use this:

var myvar = document.getElementById("selectboxid");
var selectedValue = myvar.options[myvar.selectedIndex].value; //This will get the selected value of the select box

example to implement this:

<html>
<head>
    <title>sample</title>
</head>
<body>
    <select name="selectboxid" id="selectboxid" onchange="alertValue()" size="1" autocomplete="off" tabindex="5">
        <option value="1">One</option>
        <option value="2">Two</option>
        <option value="3">Three</option>
        <option value="4">Four</option>
    </select>
    <script type="text/javascript">
    function alertValue() //this function will only be called when the value of select changed.
    {
        var myvar = document.getElementById("selectboxid");
        var selectedValue = myvar.options[myvar.selectedIndex].value; //This will get the selected value of the select box
        alert(selectedValue);
    }
    </script>
</body>
</html>

edited Oct 25 '12 at 00:59

answered Oct 25 '12 at 00:25

Jeff Robert Dagala

613
7
19

I just tried this and am getting the error "SCRIPT5007: Unable to get value of the property 'options': object is null or undefined ..." – Nate Oct 25 '12 at 00:29
what browser are you using? when did you call the javascript? before or after the select element? – Jeff Robert Dagala Oct 25 '12 at 00:31
It appears that the element in question is not present when the code is run. Jeff's suggestion works as expected in jsFiddle (in Chrome). – Kevin Boucher Oct 25 '12 at 00:31
@JeffRobertDagala - I'm trying it in IE9 and Chrome. The javascript is in the html file at the bottom of the page. – Nate Oct 25 '12 at 00:36
@KevinBoucher - the code is run when a checkbox is checked, so the page has been loaded for a long time when the code runs. – Nate Oct 25 '12 at 00:37
can you post your script when the checkbox was checked? – Jeff Robert Dagala Oct 25 '12 at 00:49
updated my answer with a sample on how to implement it. it works on IE9 and Chrome Version 22 – Jeff Robert Dagala Oct 25 '12 at 01:01
Jeff, thanks so much for your help. I found a stupid little typo in my code that was breaking it. After correcting that, your code worked. Thanks! – Nate Oct 25 '12 at 01:13

Can't get value of select box in IE or Chrome?

1 Answers1