JavaScript解析json字符串-蒲公英云

JavaScript解析json字符串

    在JavaWeb的开发过程中对json字符串的解析是比较常见的，那么怎么借助JavaScript去解析json字符串呢？这里直接上代码：
    代码一一个 Servlet
package com.ghj.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.google.gson.Gson;
public class JsonServlet extends HttpServlet {
    private static final long serialVersionUID = -699926309344319475L;
    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/json;charset=utf-8");
        PrintWriter out = response.getWriter();
        Map<String, List<String>> dataMap = new HashMap<String, List<String>>();
        List<String > gradeList = new ArrayList<String>();//年级
        gradeList.add("初中一年级");
        gradeList.add("初中二年级");
        gradeList.add("初中三年级");
        dataMap.put("gradeList", gradeList);
        List<String> courseList = new ArrayList<String>();//课程
        courseList.add("语文");
        courseList.add("数学");
        courseList.add("物理");
        dataMap.put("courseList", courseList);
        out.write(new Gson().toJson(dataMap));
        out.flush();
        out.close();
    }
}
    说明：这里使用了gson-2.2.2.jar包
    代码二——一个jsp
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%
    String basePath = request.getScheme() + "://" + request.getServerName() + ":" + request.getServerPort() + request.getContextPath() + "/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
    <head>
        <title>首页</title>
        <script type="text/javascript" src="<%=basePath%>js/jquery-1.7.2.js"></script>
        <script type="text/javascript">
            $(function(){
                $("#json").click(function(){
                    $.ajax({
                        type: "POST",
                          url: "<%=basePath%>JsonServlet",
                        success: function(data){
                              var grades = data.gradeList;
                            for(var index in grades){//年级
                                console.log(grades[index]);
                            }
                            var courses = data.courseList;
                            for(var index in courses){//课程
                                console.log(courses[index]);
                            }
                        },
                        error:function(){
                            alert("数据请求失败！");
                        }
                    });
                });
            });
        </script>
    </head>
    <body>
        <button id="json">JavaScript解析JSON字符串</button>
    </body>
</html>
    说明：上面代码没有借助JavaScript中的eval来解析json字符串