1.首先下载json所以依赖的包， Json-lib 最新版 json-lib-2.3-jdk15.jar，其官方网站是：http://json-lib.sourceforge.net/可以直接download，细心的你会发现其网站页面里面有提示它还需要其他包：
Json-lib requires (at least) the following dependencies in your classpath:
•jakarta commons-lang 2.4
•jakarta commons-beanutils 1.7.0
•jakarta commons-collections 3.2
•jakarta commons-logging 1.1.1
•ezmorph 1.0.6
下载地址分别是：
http://commons.apache.org/lang/
http://commons.apache.org/beanutils/
http://commons.apache.org/collections/
http://commons.apache.org/logging/
http://ezmorph.sourceforge.net/
2.首先先见一个小web项目
User类：
package com.json;
public class User {
String username;
String password;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
servlet :
package com.json;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.sf.json.JSONArray;
public class TestJson extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request,response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html");
String str= =request.getParameter("name");//得到ajax传递过来的paramater
PrintWriter out = response.getWriter();
List list = new ArrayList();//传递List
Map m=new HashMap();//传递Map
User u1=new User();
u1.setUsername("zah");
u1.setPassword("123");
User u2=new User();
u2.setUsername("ztf");
u2.setPassword("456");
list.add(u1); //添加User对象
list.add(u2); //添加User对象
m.put("u1", u1);
m.put("u2", u2);
JSONArray jsonArray2 = JSONArray.fromObject( list );
//把java数组转化成转化成json对象
JSONObject jo=JSONObject.fromObject(m);
//转化Map对象
out.print(jsonArray2);//返给ajax请求
out.print(jo);//返给ajax请求
}
}
ajax实现:
<script type="text/javascript" src="js/jquery.js"></script>
<script type="text/javascript">
function test(){
$.ajax({
type:"POST", //请求方式
url:"testjson", //请求路径
cache: false,
data:"name=zah", //传参
dataType: ‘json‘, //返回值类型
success:function(json){
alert(json[0].username+" " json[0].password); //弹出返回过来的List对象
}
});
}
</script>
<body>
<input type="button" name="b" value="测试" onclick=test()>
</body>
输出：zah 123
访问Map的话直接把返回函数改成如下即可：
success:function(json){
alert(json.u1.username)
}
时间： 2024-10-20 07:51:25