I am having a problem passing a variable from PHP to Javascript and getting
my JS function to recognize a form element object. I am trying to use the
selection of a particular option in a dropdown menu to control the
visibility of another form control element (another select box). In other
words, when the user selects the third option in the menu named "petsubtype"
, the menu named "chonpetsub" should become visible. Similarly, if the third
option is deselected, the latter menu should once again disappear. When I
click on any of the options in the first menu (i.e., "petsubtype"), I get a
Javascript warning that says "elementname.length is null or not an object".
Any help would be greatly appreciated.
Thanks in advance, Bill
//**************************************************************************
***************************
function PetSubToggle(id, elementname, form) {
alert("Function call here successful");
for(var i=0; i<form.elementname.length; i++){
//alert("starting to cycle through loop");
if (form.elementname.options[i].selected == true){
//alert("a selected choice is true");
if(i==3){
if(document.getElementById(id).style.visibility){
if(document.getElementById(id).style.getAttribute("visibility")=="hidden"){
document.getElementById(id).style.setAttribute("visibility",visible)}
else
if(document.getElementById(id).style.getAttribute("visibility")=="visible"){
document.getElementById(id).style.setAttribute("visibility",hidden)}
else {
alert("Your browser does not support proper display of this menu, please
upgrade or change browsers.")};
}
}
}
}
return false
}
</SCRIPT>
<!--
//**************************************************************************
****************************
-->
<SCRIPT language="php">
require 'dhtml_functions.inc';
require 'meteor_data_arrays.inc';
//**************************************************************************
****************************
$petsubname="petsubtype"; //used below to assign an name the the petsub
div id
$elementname="chonpet"; //add column for petrologic
types
$elementsarray="$chon_pet"; //an associative array
echo "<form>";
echo "<table><tr><td>";
echo "<select name='$petsubname'
id='$elementname'
multiple
size='5'
onChange='PetSubToggle($petsubname, $elementname,
this.form)'>";
//display petro types in option list, beginning with select all
echo "<option value='$chon_pet[8]' selected>$chon_pet[8]</option>";
echo "<option value='$chon_pet[1]'>$chon_pet[1]</option>";
echo "<option value='$chon_pet[2]'>$chon_pet[2]</option>";
echo "<option value='$chon_pet[3]'>$chon_pet[3]</option>";
echo "<option value='$chon_pet[4]'>$chon_pet[4]</option>";
echo "<option value='$chon_pet[5]'>$chon_pet[5]</option>";
echo "<option value='$chon_pet[6]'>$chon_pet[6]</option>";
echo "<option value='$chon_pet[7]'>$chon_pet[7]</option>";
echo "</select>";
//**************************************************************************
****************************
echo "</td><td>";
echo "<div id='$petsubname'
style='position:relative;left:0px;top:0px;visibility:hidden'>";
echo "<select name='chonpetsub' id='chonpetsub' multiple size='5'>";
echo "<option value='1'>3.1</option>";
echo "<option value='2'>3.2</option>";
echo "<option value='3'>3.3</option>";
echo "<option value='4'>3.4</option>";
echo "<option value='5'>3.5</option>";
echo "<option value='6'>3.6</option>";
echo "<option value='7'>3.7</option>";
echo "<option value='8'>3.8</option>";
echo "<option value='9'>3.9</option>";
echo "<option value='10'>All Types</option>";
echo "</select>";
echo "</div>";
echo "</td></tr></table></form>";
//**************************************************************************
****************************
</SCRIPT>
--
PHP General Mailing List (http://www.php.net/)
To unsubscribe, visit: http://www.php.net/unsub.php
