Thanks to quick reply 
In the view source is like this. (I add '<?php' in the first line just to make it coloured)
<?php
<form action="/ycms/innerSite/Drop" method="post">
<div class="simple">
<select name="sectionid" id="sectionid">
<option value="1">Wellcome Page</option>
<option value="2">About Us</option>
<option value="3">News</option>
<option value="4">Services</option>
<option value="5">Solutions</option>
<option value="6">Projects</option>
<option value="7">Documentation</option>
<option value="8">F.A.Q</option>
</select></div>
<div class="simple">
<select id="id" name="id">
</select></div>
<div class="action">
<input type="submit" name="yt0" value="Submit"/></div>
</form>
<script type="text/javascript">
/*<![CDATA[*/
jQuery(document).ready(function() {
function generateSelect(value){ var o = ''; for(key in value) { o += '<option value="' + key + '">' + value[key] + '</option>';} if(o!=''){ jQuery(o).prependTo("#id"); }}
function getData(value) { jQuery("#id").empty(); jQuery.getJSON('/ycms/innerSite/LoadCategories', { value: value }, generateSelect);}
jQuery("#sectionid").change(function () { getData(this.value); });var n=jQuery("#sectionid").attr('value'); getData(n);
});
/*]]>*/
</script>
Here is my database table:
<?php
--
-- Table structure for table `categories`
--
CREATE TABLE IF NOT EXISTS `categories` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(255) NOT NULL DEFAULT '',
`section` int(11) NOT NULL,
`published` tinyint(1) NOT NULL DEFAULT '0',
PRIMARY KEY (`id`),
KEY `cat_idx` (`section`,`published`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 AUTO_INCREMENT=9 ;
--
-- Dumping data for table `categories`
--
INSERT INTO `categories` (`id`, `name`, `section`, `published`) VALUES
(1, 'Why we are best', 1, 1),
(2, 'About Us', 2, 1),
(3, 'News', 3, 1),
(4, 'Services', 4, 1),
(5, 'Solutions', 5, 1),
(6, 'Current Projects', 6, 1),
(7, 'Documentation', 7, 1),
(8, 'F.A.Q', 8, 1);
-- --------------------------------------------------------
--
-- Table structure for table `sections`
--
CREATE TABLE IF NOT EXISTS `sections` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(255) NOT NULL DEFAULT '',
`published` tinyint(1) NOT NULL DEFAULT '0',
PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 AUTO_INCREMENT=9 ;
--
-- Dumping data for table `sections`
--
INSERT INTO `sections` (`id`, `name`, `published`) VALUES
(1, 'Wellcome Page', 1),
(2, 'About Us', 1),
(3, 'News', 1),
(4, 'Services', 1),
(5, 'Solutions', 1),
(6, 'Projects', 1),
(7, 'Documentation', 1),
(8, 'F.A.Q', 1);
Like you see, I want to load Categories base of selected section.
How to make controller and view in this case?