JS-Noob needs help!

hi;

i have a form with 2 fields:

color:
<select name="color">
<option value=1>red</option>
<option value=2>black</option>
<option value=3>blue</option>
<option value=4>white</option>
<option value=3>yellow</option>
</select>


transparency:
<input type="text" name="transparency" value="">

Code (markup):

i want to disable the transparency field if color is not 1, 3 or 4; could someone help me please?

 

I didn't test this, but it should work. If not it should point you in the right direction. Make sure to check the values of your options, I saw you had 2 options with value=3. Not sure if this was supposed to be like that, or if that 2nd value=3 was supposed to be value=5. Also, you will need to give your form the name attribute and change formname in the javascript to whatever you name your form. Hope this helps.

<script language="javascript">
	function chkColor(selObj) {
		switch(selObj.options[selObj.selectedIndex].value) {
			case 2:
				formname.transparency.disabled = true;
				break;
			case 5:
				formname.transparency.disabled = true;
				break;
		}
	}
</script>

color:
<select name="color" onchange="chkColor(this);">
<option value=1>red</option>
<option value=2>black</option>
<option value=3>blue</option>
<option value=4>white</option>
<option value=5>yellow</option>
</select>


transparency:
<input type="text" name="transparency" value="">

Code (markup):

 

I forgot that in the code above it will only set the transparency field to disabled, but never switch back to enabled if 1, 3, or 4 are selected. This should fix that.

<script language="javascript">
	function chkColor(selObj) {
		switch(selObj.options[selObj.selectedIndex].value) {
			case 1:
				formname.transparency.disabled = false;
				break;
			case 2:
				formname.transparency.disabled = true;
				break;
			case 3:
				formname.transparency.disabled = false;
				break;
			case 4:
				formname.transparency.disabled = false;
				break;
			case 5:
				formname.transparency.disabled = true;
				break;
		}
	}
</script>

Code (markup):