XMLHttpRequest
创建XMLHttpRequest对象 var xmlhttp; if (window.XMLHttpRequest) {// code for IE7+, Firefox, Chrome, Opera, Safari xmlhttp=new XMLHttpRequest(); } else {// code for IE6, IE5 xmlhttp=new ActiveXObject("Microsoft.XMLHTTP"); } 发送请求 //get方式 xmlhttp.open("GET","test1.txt",true); xmlhttp.send(); //post方式 xmlhttp.open("POST","ajax_test.asp",true); xmlhttp.setRequestHeader("Content-type","application/x-www-form-urlencoded"); xmlhttp.send("fname=Bill&lname=Gates"); 异步 - True 或 False? True时 xmlhttp.onreadystatechange=function() { if (xmlhttp.readyState==4 && xmlhttp.status==200) { document.getElementById("myDiv").innerHTML=xmlhttp.responseText; } } xmlhttp.open("GET","test1.txt",true); xmlhttp.send(); False时 xmlhttp.open("GET","test1.txt",false); xmlhttp.send(); document.getElementById("myDiv").innerHTML=xmlhttp.responseText; //回调 xmlhttp.onreadystatechange=function() { if (xmlhttp.readyState==4 && xmlhttp.status==200) { document.getElementById("myDiv").innerHTML=xmlhttp.responseText; } }