Event.observe(window, 'load', init, false);
function init(){
     Event.observe('parentcatbox', 'change', parentcat, false);
	 Event.observe('categorybox', 'change', category, false);	 	
	 Event.observe('continent', 'change', continent, false);
}
function parentcat(){
     var url = '/ajax.php';
     var pars = 'parentid='+escape($F('parentcatbox'));
     var target = 'categorybox';
     var myAjax = new Ajax.Updater(target, url, {method: 'get', parameters: pars});	 
}
function category(){
     var url = '/ajax.php';
     var pars = 'categoryid='+escape($F('categorybox'));
     var target = 'parentcatbox';
     var myAjax = new Ajax.Updater(target, url, {method: 'get', parameters: pars});
	 if($F('categorybox')==0){
		 var url = '/ajax.php';
		 var pars = 'parentid=0';
		 var target = 'categorybox';		 
		 var myAjax = new Ajax.Updater(target, url, {method: 'get', parameters: pars});
	 }
}
function continent(){
	 var url = '/ajax.php';
	 var pars = 'continentid='+escape($F('continent'));
	 var target = 'country';
	 var myAjax = new Ajax.Updater(target, url, {method: 'get', parameters: pars});
	 
	 var pars = 'countryid=0';
	 var target = 'province';
	 var myAjax = new Ajax.Updater(target, url, {method: 'get', parameters: pars});	 
	 
	 var pars = 'provinceid=0';
	 var target = 'city';
	 var myAjax = new Ajax.Updater(target, url, {method: 'get', parameters: pars});	 		 	  
}