request.getAttribute
Posted XuGuobao
tags:
篇首语：本文由小常识网(cha138.com)小编为大家整理，主要介绍了request.getAttribute相关的知识，希望对你有一定的参考价值。
1、在Struts2中，通常是先进入jsp页面，再进入action中；如果要实现action页面所得信息的反向输入到上述的jsp页面中，就可以使用request.getAttribute（）；
2、request.setAttribute()和getAttribute()方法传递的数据只会存在于Web容器内部
3、部分代码演示
（1）jsp代码
1 <html> 2 <head> 3 <title></title> 4 </head> 5 6 <body> 7 <h3>用户登录</h3> 8 <hr/> 9 10 <form action="Login.action" method="post"> 11 <table> 12 <tr> 13 <td style="width:60px;"><label for="username$text">身份：</label></td> 14 <td> 15 <select name="Type" id="Type" style="width:148px;"> 16 <option value="请选择">请选择</option> 17 <option value="系统管理员">系统管理员</option> 18 <option value="楼宇管理员">楼宇管理员</option> 19 <option value="学生">学生</option> 20 </select> 21 </td> 22 </tr> 23 <tr> 24 <td>用户名</td> 25 <td><input type="text" name="Username" onvalidation="onUserNameValidation" 26 class="mini-textbox" 27 required style="width:150px;"></td> 28 </tr> 29 <tr> 30 <td>密码</td> 31 <td><input type="password" name="Password" onvalidation="onUserNameValidation" 32 class="mini-textbox" 33 required style="width:150px;"></td> 34 </tr> 35 <tr> 36 <td colspan="2"> 37 <input type="submit" value="登录"> 38 <input type="reset" value="重置"> 39 </td> 40 </tr> 41 <%if(request.getAttribute("Msg")!=null){%> 42 <%=request.getAttribute("Msg")%> 43 <%}%> 44 </table> 45 </form> 46 </body> 47 </html>
（2）action代码
1 package com.action; 2 3 import com.factory.StudentDAOFactory; 4 import com.opensymphony.xwork2.ActionContext; 5 import com.vo.Student; 6 7 public class Login { 8 private String Type; 9 private String Username; 10 private String Password; 11 private String Msg; 12 public String getType() { 13 return Type; 14 } 15 public void setType(String type) { 16 Type = type; 17 } 18 public String getUsername() { 19 return Username; 20 } 21 public void setUsername(String username) { 22 Username = username; 23 } 24 public String getPassword() { 25 return Password; 26 } 27 public void setPassword(String password) { 28 Password = password; 29 } 30 public String getMsg() { 31 return Msg; 32 } 33 public void setMsg(String msg) { 34 Msg = msg; 35 } 36 public String execute()throws Exception{ 37 if(Type.equals("学生")){ 38 Student student = new Student(); 39 student.setStudent_Number(getUsername()); 40 student.setStudent_Password(getPassword()); 41 if(StudentDAOFactory.getIStudentDAOInstance().studentLogin(student)){ 42 ActionContext.getContext().getSession().put("student_number", student.getStudent_Number()); 43 ActionContext.getContext().getSession().put("student_name", student.getStudent_Name()); 44 ActionContext.getContext().getSession().put("student_sex", student.getStudent_Sex()); 45 ActionContext.getContext().getSession().put("student_domitory", student.getStudent_Domitory()); 46 ActionContext.getContext().getSession().put("student_password", student.getStudent_Password()); 47 ActionContext.getContext().getSession().put("student_absenceDate", student.getStudent_AbsenceDate()); 48 return "success"; 49 }else{ 50 Msg = "用户名或者密码错误"; 51 return "error"; 52 } 53 }else{ 54 Msg = "身份选择错误！"; 55 return "error"; 56 } 57 } 58 }
以上是关于request.getAttribute的主要内容，如果未能解决你的问题，请参考以下文章
java Web中在啥时候用request.getAttribute()？何时用request.getParameter()呢？
request.getAttribute（） session.getAttribute() application.getAttribute() 的getAttribute方法有区别
request.getParameter() 和request.getAttribute() 区别
request.getAttribute()与request.setAttribute()