Java Web中,js外部文件如何获取后台的变量呢?
项目使用spring MVC框架,
IDE:eclipse;
使用maven构建
控制器(OsTypeController.Java)如下:
- package com.ct.web.controller;
- import java.util.Date;
- import java.util.List;
- import org.springframework.beans.factory.annotation.Autowired;
- import org.springframework.stereotype.Controller;
- import org.springframework.ui.Model;
- import org.springframework.web.bind.annotation.RequestMapping;
- import org.springframework.web.bind.annotation.SessionAttributes;
- import com.ct.dao.OsTypeDao;
- import com.ct.entity.OsType;
- import com.time.util.TimeHWUtil;
- @Controller
- @RequestMapping("/osType")
- @SessionAttributes("practiceWay")
- public class OsTypeController {
- private OsTypeDao osTypeDao;
- private String redirectViewAll="redirect:/osType/viewAll";
- @RequestMapping(value = "/add")
- public String addInputOsType(String practiceWay,Model model){
- model.addAttribute("practiceWay", practiceWay);
- System.out.println("practiceWay:"+practiceWay);
- return "osType/addOSType";
- }
- /******************************************************************/
- public OsTypeDao getOsTypeDao() {
- return osTypeDao;
- }
- @Autowired
- public void setOsTypeDao(OsTypeDao osTypeDao) {
- this.osTypeDao = osTypeDao;
- }
- }
控制器方法addInputOsType 对应的页面(addOSType.jsp)如下:
- <?xml version="1.0" encoding="UTF-8" ?>
- <%@ page language="java" contentType="text/html; charset=UTF-8"
- pageEncoding="UTF-8"%>
- <%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
- <%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions"%>
- <%
- String path = request.getContextPath();
- String basePath = request.getScheme() + "://"
- + request.getServerName() + ":" + request.getServerPort()
- + path + "/";
- %>
- <!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>
- <base href="<%=basePath%>">
- <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
- <title>Insert title here</title> <script type="text/javascript"
- src="<%=path%>/static/js/Module.js"></script>
- <script type="text/javascript" src="<%=path%>/static/js/common_util.js"></script>
- <script type="text/javascript" src="<%=path%>/static/js/test.js"></script>
- </head>
- <body>
- <center>
- <h1><span id="titleSpan">add </span> </h1>
- <input type="hidden" value="${sessionScope.practiceWay}" name="hidpracticeWay" />
- <a href="javascript:history.go(-1)" >return </a> |
- <a href="index.jsp" >index</a> | <a href="osType/viewAll">view all</a>
- <form action="osType/save" name="inputform" >
- <table>
- <tr>
- <td>os name:</td>
- <td><input type="text" name="name" /></td>
- </tr>
- <tr>
- <td colspan="2" ><input type="submit"
- value=" o k " id="submit_btn" /></td>
- </tr>
- </table>
- <div id="hidden_div"></div>
- </form>
- </center>
- </body>
- </html>
其中外部js文件(test.js)如下:
- alert("111:${sessionScope.practiceWay}");
- window.onload =function a()
- {
- alert("method:a");
- alert("444:${sessionScope.practiceWay}");
- alert("hid:"+document.getElementsByName("hidpracticeWay")[0].value);
- };
在浏览器中输入http://localhost:8088/demo_channel_terminal/osType/add?practiceWay=random
运行结果:
对应的是外部js文件(test.js)的执行结果。
所以我们可以得出结论:
在外部js文件获取后台变量的方式就是通过获取页面隐藏域的值。
具体步骤:
(1)把后台变量设置到页面隐藏域中,例如
- <input type="hidden" value="${sessionScope.practiceWay}" name="hidpracticeWay" />
(2)在外部js文件中获取隐藏域的值,例如
- alert("hid:"+document.getElementsByName("hidpracticeWay")[0].value);
那么在jsp页面中的js代码中如何获取后台变量的值呢?
请参阅我的下一篇日志