How do I dynamically modify the contents of a list box?

[billygronk]

I want to modify the contents of a drop down list box based on a previous selection of a user so that when they choose an option from the first list box the contents will change in the second. Can anyone help?

 

[robherc]

The following script SHOULD insert a value "value" as a new last option at the end of the first &lt;select&gt; in the first &lt;form&gt; on a web page when the function insertvalue(value) is called (please let me know if you find any glitches...POST ANY ERROR MESSAGES):<br>
<br>
&lt;script language=JavaScript&gt;<br>
&lt;!--;<br>
function insertvalue(value)<br>
{<br>
var leng=document.forms[0].selects[0].length<br>
document.forms[0].selects[0].options[leng]=value<br>
}<br>
//--&gt;<br>
&lt;/script&gt;