不用jQuery的ajax流程
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Insert title here</title> </head> <script> /* * 1.大致的流程 * * 创建核心对象 * * 绑定一个函数 * * 打开和服务端连接 * * 发送数据 * * 处理函数 成本的付出 * 2.核心对象的5种状态分别代表的含义 */ function GetXmlHttpObject() { var xmlHttp=null; try { // Firefox, Opera 8.0+, Safari xmlHttp=new XMLHttpRequest(); } catch (e) { // Internet Explorer try { xmlHttp=new ActiveXObject("Msxml2.XMLHTTP"); } catch (e) { xmlHttp=new ActiveXObject("Microsoft.XMLHTTP"); } } return xmlHttp; } function fn(){ //1.创建对象 var xmlHttpRequest=GetXmlHttpObject(); //2.绑定函数 xmlHttpRequest.onreadystatechange=fm; //3.打开 xmlHttpRequest.open("get","test.jsp",true); //4.发送 xmlHttpRequest.send(); //5.处理绑定函数 function fm(){ if (xmlHttpRequest.readyState==4) { if (xmlHttpRequest.status==200) { document.getElementById('dv').innerHTML=xmlHttpRequest.responseText; } else { alert("Problem retrieving data:" + xmlHttpRequest.statusText); } } } } </script> <body> <button onclick="fn()">按钮</button> <div id="dv"></div> </body> </html>
test.jsp
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <% out.println("AAAAAA"); %>
基于jQuery的ajax
xml格式的数据
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/ TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title></title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <!-- 引入jQuery --> <script src="../scripts/jquery-1.3.1.js" type="text/javascript"></script> <script language="javascript" > $(function(){ $("#send").click(function(){
//获取id是username和content的值，回调函数dt的值是返回的数据 $.post("demo2.jsp",{"username":$("#username").val(),"content":$("#content").val()},function(dt){ //alert(dt); //保证第一行的XML数据没有空行 var um=$(dt).find("comments comment").attr("username"); var con=$(dt).find("comments content").text(); $("#resText").html(um+" "+con); },"xml"); }); }); </script> </head> <body> <form id="form1"> <p>评论:</p> <p>姓名: <input type="text" name="username" id="username" /></p> <p>内容: <textarea name="content" id="content" ></textarea></p> <p><input type="button" id="send" value="提交"/></p> </form> <div class='comment'>已有评论：</div> <div id="resText" > </div> </body> </html>
demo2.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><% //注意空行问题 String username = request.getParameter("username"); String content = request.getParameter("content"); response.setContentType("text/xml"); out.println("<?xml version='1.0' encoding='UTF-8'?>"); out.println("<comments>"); out.println("<comment username='"+username+"'>"); out.println("<content>"+content+"</content>"); out.println("</comment>"); out.println("</comments>"); %>
json格式的数据
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/ TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title></title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <!-- 引入jQuery --> <script src="../../jquery-1.4.2.js" type="text/javascript"></script> <script language="javascript" > $(function(){ $("#send").click(function(){ //$.post("demo3.jsp",{"username":$("#username").val(),"content":$("#content").val()},function(dt){ // 将JSON格式的字符串转换为JS对象 // var dd=eval("("+dt+")") // alert(dd.username); //alert(dd.content); //}); $.post("demo3.jsp",{"username":$("#username").val(),"content":$("#content").val()},function(dt){ alert(dt); $("#resText").html(dt.username+" "+dt.content); },"json"); }); }); </script> </head> <body> <form id="form1"> <p>评论:</p> <p>姓名: <input type="text" name="username" id="username" /></p> <p>内容: <textarea name="content" id="content" ></textarea></p> <p><input type="button" id="send" value="提交"/></p> </form> <div id="resText" > </div> </body> </html>
demo3.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><% String username = request.getParameter("username"); String content = request.getParameter("content"); System.out.print("{"username":""+username+"","content":""+content+""}"); out.print("{"username":""+username+"","content":""+content+""}"); %>
这是我之前项目中总用到的类型，重点：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/ TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title></title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <!-- 引入jQuery --> <script src="../../jquery-1.4.2.js" type="text/javascript"></script> <script language="javascript" > $(function(){ /* * $.ajax({url:'',data:{},type:'',dataType:'json',success:function(dt){},error:function(){}}); */ $("#send").click(function(){ //$.ajax(); ==> $.ajax({}); ===>$.ajax({k1:v1,k2:v2,k3:v3.....}); $.ajax({ //请求的路径 url:'demo.jsp', //发送到服务端的数据 data:{username:$("#username").val(),content:$("#content").val()}, //请求的类型 type:'post', //响应回的数据 格式 dataType:'json', //成功之后处理的函数 success:function(dt){ //alert(dt); $("#resText").html(dt.username+" "+dt.content); }, //失败之后处理的函数 error:function(){ alert("Fail"); } }); }); }) </script> </head> <body> <form id="form1"> <p>评论:</p> <p>姓名: <input type="text" name="username" id="username" /></p> <p>内容: <textarea name="content" id="content" ></textarea></p> <p><input type="button" id="send" value="提交"/></p> </form> <div class='comment'>已有评论：</div> <div id="resText" > </div> </body> </html>
demo.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><% String username = request.getParameter("username"); String content = request.getParameter("content"); out.print("{"username":""+username+"","content":""+content+""}"); %>