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document.forms[0].mounting_type[0].disabled = true;
document.forms[0].mounting_type[1].disabled = true;
document.forms[0].output_position[0].disabled = true;
document.forms[0].output_position[1].disabled = true;
document.forms[0].output_position[2].disabled = true;
document.forms[0].shaft_type[0].disabled = true;
document.forms[0].shaft_type[1].disabled = true;
document.forms[0].shaft_type[2].disabled = true;
I know that this is exactly the kind of basic repetitive stuff that good programming should eliminate. So how would I do this here? One problem is that I'm confused between a string and a variable name. Can I use a string to create a variable name dynamically?
var radioGroups = ("mounting_type","output_position","shaft_type");
document.forms[0].radioGroups[0][0].disabled = true;
I don't think I can substitute a string in the middle of an object reference like that, or can I? It would allow me to build a more elegant loop, something like this:
for(var i=0;i<radioGroups.length;i++) {
var thisRadioGroup = document.forms[0].radioGroups[i];
for(var j=0;j<thisRadioGroup.length;j++) {
thisRadioGroup[j].disable = true;
}
}
Needless to say this doesn't work but what is the problem in my logic?
var radioGroups = ("mounting_type","output_position","shaft_type");
for(var i=0;i<radioGroups.length;i++) {
[b]var thisRadioGroup = document.getElementsByName(radioGroups[i]);[/b]
for(var j=0;j<thisRadioGroup.length;j++) {
thisRadioGroup[j].disable = true;
}
}getElementsByName takes a string and returns an array. It seems like just what's called for here.
I thought it might be some kind of browser support issue with getElementsByName(). Also, I'm firing this script with the onload event, and perhaps that causes some problem?
As an interesting aside, if you were trying to code it using the original document.forms[0].mounting_type[0].disabled method is there actually any way to read a string into a variable name in Javascript? (I accept that your getElementsByName method is better for the job, if I could get it to work, I'm just curious).
you may find this method of interest...
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head>
<title>radio disable</title>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"/>
<script type="text/javascript">
<!--
function shutOff() {
var radio=document.getElementsByTagName('input');
for(c=0;c<radio.length;c++) {
if(radio[c].name=="mounting_type"¦¦radio[c].name=="output_position"¦¦radio[c].name=="shaft_type") {
radio[c].disabled=true;
}
}
}
onload=shutOff;
//-->
</script>
</head>
<body>
<form action="#">
<div>
<input type="radio" name="mounting_type"/>
<input type="radio" name="output_position"/>
<input type="radio" name="shaft_type"/>
<input type="radio" name="foo"/>
<input type="radio" name="mounting_type"/>
<input type="radio" name="output_position"/>
<input type="radio" name="shaft_type"/>
<input type="radio" name="foo"/>
</div>
</form>
</body>
</html>
birdbrain
radio[c][i].disabled = true;
instead of
radio[c].disabled = true;
?
By the way, I think you can check 'disable [codes]' in your post if you want to include extra characters? Does that help? ¦¦¦¦¦
As an interesting aside, if you were trying to code it using the original document.forms[0].mounting_type[0].disabled method is there actually any way to read a string into a variable name in Javascript?
You can use the eval method to make your Strings recognized as objects on the page. However, getElementsByName is much neater and I'm sure you can get it working with a little debugging. Whichever you choose, good luck. :)
