实例:
一、数据集所在jsp页面out.jsp,代码如下
<%@page contentType="text/plaincharset=UTF-8"
language="java"
import="java.io.*,java.net.*,java.util.*"
buffer="8kb"
session="false"
autoFlush="true"
%>
<%
String jsonData="{data:[{id:200901,name:'name1'},{id:200902,name:'name2'},{id:200903,name:'姓名3'},{id:200904,name:'姓名4'},{id:200905,name:'姓名5'}]}"
//out.clear()
out.write(jsonData)
%>
二、js处理页面
(1)
<!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>
<title>test</title>
<meta http-equiv="Content-Type" content="text/htmlcharset=UTF-8"/>
<script type="text/javascript" language="javascript" src="js/jquery.js"></script>
<script type="text/javascript">
function getOut(){
var s=''
$.ajax({
type:'get',//请求方式
url:'out.jsp?id='+Math.random(), // AJAX HTTP请求接口
data:'',//提交到服务器接口的参数 比如'{cid:0405}',结果为out.jsp?cid=0405格式
dataType:'json',//请求类型为json, 更多见jquery doc文档
timeout:7000,//请求超时后停止请求
success: function(json){
var d=json.data
$.each(d,function(i){
s+=('<p>id:'+d[i].id +' | name:'+d[i].name+'</p><hr/>')
})
$('#out').html(s)}})
}
</script>
</head>
<body style="margin:20pxtext-align:centerbackground:#E5E5E5">
<input type="text" name="getdata" onclick="getOut()"/>
<div id="out">
</div>
</body>
</html>
(2)
<!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">
<%@ page language="java" contentType="text/htmlcharset=utf-8"%>
<head>
<script type="text/javascript" src="js/jquery-1.3.2.min.js"></script>
<script>
function showStudent(){
var s=''
$.getJSON("out.jsp?id="+Math.random(),function(json){
var d=json.data
for(var i=0i<d.lengthi++){
s+=('<p>id:'+d[i].id +' | name:'+d[i].name+'</p><hr/>')
}
$('#content').html(s)
})
}
</script>
</head>
<body>
<input type="button" value="获取学院信息" onclick="showStudent()" />
<div id="content"></div>
</body>
</html>
总结:
(1)有时候总是出现错误,原因在于——json数据格式有问题,前端$.getJSON()方法并没有什么错误。
(2)相对来说,$ajax(option)方法使用比较灵活,可以用在比较复杂的情况。
varjson
=
{
contry:{
area:{
man:"12万",
women:"10万"
}
}
}
//方式一:使用eval解析
var
obj
=
eval(json)
alert(obj.constructor)
alert(obj.contry.area.women)
//方式二:使用Funtion函数
var
strJSON
=
"{name:'json
name'}"//得到的JSON
var
obj
=
new
Function("return"
+
strJSON)()//转换后的JSON对象
alert(obj.name)//json
name
alert(obj.constructor)
//复杂一点的json数组数据的解析
var
value1
=
[{"c01":"1","c02":"2","c03":"3","c04":"4","c05":"5","c06":"6","c07":"7","c08":"8","c09":"9"},
{"c01":"2","c02":"4","c03":"5","c04":"2","c05":"8","c06":"11","c07":"21","c08":"1","c09":"12"},
{"c01":"5","c02":"1","c03":"4","c04":"11","c05":"9","c06":"8","c07":"1","c08":"8","c09":"2"}]
var
obj1
=
eval(value1)
alert(obj1[0].c01)
//复杂一点的json的另一种形式
var
value2
=
{"list":[
{"password":"1230","username":"coolcooldool"},
{"password":"thisis2","username":"okokok"}],
"array":[{"password":"1230","username":"coolcooldool"},{"password":"thisis2","username":"okokok"}]}
var
obj2
=
eval(value2)
alert(obj2.list[0].password)
==========================================js 中读取JSON的方法探讨
js读取JSON的方法我接触到的有两种:
方法一:函数构造定义法返回
var strJSON = "{name:'json name'}"//得到的JSON
var obj = new Function("return" + strJSON)()//转换后的JSON对象
alert(obj.name)//json name
方法二:js中著名的eval函数
var strJSON = "{name:'json name'}"//得到的JSON
var obj = eval( "(" + strJSON + ")" )//转换后的JSON对象
alert(obj.name)//json name
第二种方法需要注意的是,对象表达式{'name':'json name'}必须用“()”扩住,否则
var strJSON = "{name:'json name'}"
var obj = eval(strJSON)
alert(obj.constructor)//String 构造函数
alert(obj.name)//undefine
必须把对象表达式扩起来eval执行才能生成一个匿名对象!