//category.php
<script language = 'javascript'>
// create ajax instance
function GetXMLHttpRequest()
{
var object = null;
if (window.XMLHttpRequest) //for mozilla,safari,opera,nets..
{
object = new XMLHttpRequest();
}
else if (window.ActiveXObject) //for IE..
{
try
{
object = new ActiveXObject("Msxml2.XMLHTTP");
}
catch(e)
{
}
if (object == null)
{
try
{
object = new ActiveXObject("Microsoft.XMLHTTP");
}
catch(e)
{
}
}
}
if (object == null)
{
alert("Your browser does not support AJAX");
}
return object;
}
var httpxx = GetXMLHttpRequest();
//Ajax for Subcategories
var url_cat = "getsubcategory.php?cid=";
// handling ajax response
function handleHttpResponse2()
{
if (httpx.readyState == 4)
{
if(httpx.status == 200)
{
document.getElementById('prepage2').style.visibility='hidden';
var results=httpx.responseText.split(",");
var oSelect1 = document.getElementById("subcategory");
oSelect1.options.length=0;
if(results[0].length==0)
{
var oOption = document.createElement("option");
oOption.value = 0;
oOption.innerHTML = "-select-";
var oSelect = document.getElementById("subcategory");
oSelect.appendChild(oOption);
}
else
{
var oOption = document.createElement("option");
oOption.value = 0;
oOption.innerHTML = "-select-";
var oSelect = document.getElementById("subcategory");
oSelect.appendChild(oOption);
for (var d=0;d < results.length ;d++)
{
var oOption = document.createElement("option");
var dd1=results[d].split("-")
oOption.value = dd1[1];
oOption.innerHTML = dd1[0];
var oSelect = document.getElementById("subcategory");
oSelect.appendChild(oOption);
}
}
}
}
}
// make ajax request
function updateCategoryState() {
var categoryValue = document.getElementById("category").value;
httpx.open("GET", url_cat + escape(categoryValue), true);
document.getElementById('prepage2').style.visibility='visible';
httpx.onreadystatechange = handleHttpResponse2;
httpx.send(null);
}
var httpx = GetXMLHttpRequest();
</script>
//category.php file where selection is made and subcategory is updated
<td width="53%">
<select id="category" name='category' onchange="updateCategoryState();" class='welcome_text'>
<option value='0' class='welcome_text'>Select Category</option>
<?php
$query1Select = "select * from tblcategories";
$query1Result = query_select($query1Select,$nRows);
while($row = mysql_fetch_object($query1Result))
{
$categoryList.="<option value='$row->id'>$row->categoryname</option>";
}
?>
</select>
</td>
<tr>
<td class="caption" align='right' class='welcome_text'>SubCategory Name </td>
<td width="53%">
<select id="subcategory" name='subcategory' class='welcome_text'>
<option value='0' class='welcome_text'>Select Subcategory</option>
<?php
$query1Select = "select * from tblsubcategories";
$query1Result = query_select($query1Select,$nRows);
while($row = mysql_fetch_object($query1Result))
{
$subcategoryList.="<option value='$row->subcategoryname'>$row->subcategoryname</option>";
}
?>
</select>
<span id="prepage2" align='center' class='welcome_text'>
<font color='#FF0000'>
Loading ... ...Please wait
</font>
</span>
</td>
</tr>
//get subcategory file .php
<?php
$str="select * from tblsubcategories where categoryid=$cid";
$res=query_select($str,$conn);
$str="";
while ($fobj=mysql_fetch_object($res))
{
$str.="$fobj->subcategoryname"."-"."$fobj->id".",";
}
$str2=substr($str,0,strlen($str)-1);
echo "$str2";
?>