if else based on a drop down menu

[leest]

Ok i am just after some advice, I  have a registration form and want to make a a field only avaliable if the user selects yes from a drop down list.  I also want to make this field a required field.  I think i know how to achieve the last part but was just wondering if any body knew if having a form field display as a result of a drop down menu was possible.

[LooieENG]

It would be best done with JavaScript

[lemmin]

Something like this:

<form>
<select onChange="if (this.value == 1) text1.style.visibility='visible'; else text1.style.visibility='hidden';">
<option value=0>No</option>
<option value=1>Yes</option>
</select>
<input id="text1" type=TEXT name="text1" style="visibility:hidden">
</form>

[leest]

HI thanks for the reply and sorry in the delay but i have been away.  Ok i am not to experienecd with javascript, the field that i want to make only visible if the value in the drop down list is the last field in my form, i have about ten form fields.  so do i change the text1 to represent the field value. 

 

Cheers

[leest]

ok, i am a bit of an idiot and when i looked at it properly it made sense, the only thing is when i upload it to my server it didn't work, the drop down list worked but when i selected yes the other field didn't work.  I know i have javascript running on my pc and so not sure why it would not work, could it be something on the server side???