Delete default value in the field

viki1967

Hi all.

I have this:

Expand|Select|Wrap|Line Numbers

 <input type="text" name="agg" size="30" value="---" readonly>
 
<select size="1" name="provv" onchange="var cc = this.options[this.selectedIndex].value; if(cc=='GAM')Popup(400,200,'GAM.asp');">

<option value="">---------</option>

<option value="GAM">GAM</option>

<option value="GBM">GBM</option>

</select>

If select GAM value open popup... I need if select GAM the value of field input type text "agg" is value null, deleted default value "---"... it's possible ?

Can you help me?