JavaScript解析json字符串

今天药忘吃喽~ 2022-08-20 14:08 187阅读 0赞

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