ajax向后台传递参数的方式

一、get方式

xmlhttp.open("GET","target？key1=value1&key2=value2",true);

xmlhttp.send(null);

二、post方式

xmlhttp.open("POST","target",true);
xmlhttp.setRequestHeader("Content-type","application/x-www-form-urlencoded;charset=UTF-8");
xmlhttp.send("type=city&selected_province_id="+selected_province_id);