function populate1() {
var List1 = document.OptionSelect.Option1;

if (List1[List1.selectedIndex].value =="1") {
button.innerHTML = '<input name="Submit" type="submit" value="Add to cart"><input name="OptionSize" type="hidden" value="1">';
}

}function AddToOptionList(OptionList, OptionValue, OptionText) {
   // Add option to the bottom of the list
   OptionList[OptionList.length] = new Option(OptionText, OptionValue);
}
function ClearOptions(OptionList) {
   for (x = OptionList.length; x >= 0; x = x - 1) {
      OptionList[x] = null;
   }
} document.write('<form name="OptionSelect" action="cart.php" method="post"><select name=\'Option1\' size=\'5\' onChange=\'populate1()\' style=\'width:150px\'><option value="1"></option></select><div id="button"><input name=\'Submit\' type=\'submit\' value=\'Add to cart\' disabled></div><input type=\'hidden\' value=\'20\' name=\'prodnum\'><input type=\'hidden\' value=\'add\' name=\'action\'></form>');