select boxes have a property called "disabled".
Depending on how you grab the element let's say:
- toggleSelect=function(el){
-
var numb=el.id.substring(7)
-
if(document.all){document.all['select'+numb].disabled=el.checked?false:true}
-
else{document.getElementByID('select'+numb).disabled=el.checked?false:true}
-
}
[HTML]<select id="select2">
<option />
option
blah blah blah
</select>
<input type="checkbox" id="checkbox2" onClick="toggleSelect(this)" />[/HTML]
notice in the html, the id's share a number....easy to cross reference the fields, then I check the checkbox's state (whether or not it's checked) to ensure we're taking the right action
