function ajax_index_product(file,content_id){
	//构造地址
	//创建ajax对象
	 var ajaxObj = null;
		 if(window.XMLHttpRequest){
			 ajaxObj = new XMLHttpRequest();
		 } else if(window.ActiveXObject){
			 ajaxObj = new ActiveXObject("Microsoft.XMLHTTP");
		 } else {
			return;
		 }
	 //状态变化
	 ajaxObj.onreadystatechange = function(){
		 if(ajaxObj.readyState == 4){
			document.getElementById(content_id).innerHTML=ajaxObj.responseText;
		 }else{
			document.getElementById(content_id).innerHTML="<div style=\"height:24px; width:450px; text-align:center;  float:left\"><img src=\"images/icon/loading_1.gif\" width=\"20\" height=\"20\" align=\"absmiddle\" />加载中...</div>";
		 }
	 }
	 
	 ajaxObj.open ('GET',file, true);
	 ajaxObj.send ('');
}