ajax中的get和post模式
Ajax 异步请求数据的方式有两种:GET 和 POST。
如果是 GET 模式,则直接将数据放置到异步请求的 URL 地址中,而 send() 方法不发送任何数据;
var queryString = "name=Liruxing&sex=man"; var url = "index.php" + queryString + "time=" + new Date().getTime(); xmlHttp.open('GET',url); xmlHttp.send(null);
如果是 POST 模式,则将数据放置在 send() 方法中发送。
1 var queryString = "name=Liruxing&sex=man"; 2 var url = "index.php" + new Date().getTime(); 3 xmlHttp.open('POST',url); 4 xmlHttp.setRequestHeader('Content-Type','application/x-www-form-urlencoded'); 5 xmlHttp.send(queryString);
下面的示例能够更清楚的演示 GET 模式和 POST 模式的区别(Ajax 结合 PHP)
index.html
<html> <head> <title>Ajax</title> <script language="javascript"> var xmlHttp; // 创建 XMLHttpRequest function createXMLHttpRequest() { if (window.ActiveXObject) { xmlHttp = new ActiveXObject('Microsoft.XMLHTTP'); } else if (window.XMLHttpRequest) { xmlHttp = new XMLHttpRequest(); } } function createQueryString() { var name = document.getElementById('name').value; var sex = document.getElementById('sex').value; var queryString = "name="+ name +"&sex=" + sex; return encodeURI(encodeURI(queryString)); // 两次编码解决中文乱码问题 } function handleStateChange() { if (xmlHttp.readyState==4 && xmlHttp.status==200) { var content = document.getElementById("content"); content.innerHTML = ''; content.innerHTML = decodeURI(xmlHttp.responseText); // 解码 } } // GET 方法 function doRequestUsingGet() { createXMLHttpRequest(); var url = "index.php?" + createQueryString() + "&time=" + new Date().getTime(); xmlHttp.open('GET', url); xmlHttp.onreadystatechange = handleStateChange; xmlHttp.send(null); } // POST 方法 function doRequestUsingPost() { createXMLHttpRequest(); var url = "index.php?time=" + new Date().getTime(); var queryString = createQueryString(); xmlHttp.open('POST', url); xmlHttp.onreadystatechange = handleStateChange; xmlHttp.setRequestHeader('Content-Type','application/x-www-form-urlencoded'); xmlHttp.send(queryString); } </script> </head> <body> <p>Name:<input type="text" id="name" /></p> <p>Sex :<input type="text" id="sex" /></p> <p><input type="button" value="GET" onClick="doRequestUsingGet()"> <input type="button" value="POST" onClick="doRequestUsingPost()"></p> <div id="content"></div> </body> </html>
index.php:
<?php header('Content-Type:text/html;Charset=GB2312'); $method = $_SERVER['REQUEST_METHOD']; if ($method == 'GET') { echo "GET:".$_GET['name'].",".$_GET['sex']; } else if ($method == 'POST') { echo "POST:".$_POST['name'].",".$_POST['sex']; } ?>