struts2 可以用ognl拿到值而不可以用el拿到值的解决方法

错误debug后

得到了There is no read method for container的错误

于是我new了一个实体类

 1 package com.unity;
 2 
 3 public class Student {
 4     private String studentName;
 5 
 6     public Student(String studentName) {
 7         this.studentName = studentName;
 8     }
 9 
10     public String getStudentName() {
11         return studentName;
12     }
13 //
14     public void setStudentName(String studentName) {
15         this.studentName = studentName;
16     }
17 }

并在action导入

 1 package com.action;
 2 
 3 import com.opensymphony.xwork2.ActionContext;
 4 import com.opensymphony.xwork2.ActionSupport;
 5 import com.opensymphony.xwork2.util.ValueStack;
 6 import com.unity.Student;
 7 
 8 public class HelloWorldAction extends ActionSupport {
 9     /**
10      * 
11      */
12     private static final long serialVersionUID = -7840227232203094654L;
13     private String studentName;
14 
15     public String getStudentName() {
16         return studentName;
17     }
18 
19     public void setStudentName(String studentName) {
20         this.studentName = studentName;
21     }
22 
23     private String password;
24 
25     public String execute() {
26         System.out.println("execute.....");
27         System.out.println("studentName:" + studentName);
28         System.out.println("password:" + password);
29         // ValueStack vs=ActionContext.getContext().getValueStack();
30         ActionContext context = ActionContext.getContext();
31         ValueStack vs = context.getValueStack();
32         // 值栈的栈顶
33 
34         Student student = new Student("111111");
35 
36         vs.push(student);
37         return "info";
38     }
39 
40     public String getPassword() {
41         return password;
42     }
43 
44     public void setPassword(String password) {
45         this.password = password;
46     }
47 }

虽然没有了There is no read method for container的错误

但是依然无法用el得到值

所以debug可以去死了

后来直接翻墙啃英文的狗屎

发现有一个版本的structs2

默认关了页面的el表达式

强制你使用ognl.........

最终解决方法

1 <%@ page language="java" contentType="text/html; charset=UTF-8"
2     pageEncoding="UTF-8" isELIgnored="false"%>

//isELIgnored 是否无视el表达式 重新设置为false

但是我后来发现第二个解决方法

同一版本的structs2在不使用maven的情况下

倒没有出现这样的问题

最后总结

为了规范,哥们在maven的情况下,用struts2就用ogln吧,硬是用el加上那句isELIgnored="false"就行了 ,

最后放点取值的方法

1         <br> 密码:${password }
2     <br> 姓名1:<%=request.getParameter("studentName")%>
3     <br> 姓名2:${studentName}
4     <br> 姓名3:
5     <s:property value="[0].studentName" />
6     <br> 姓名4:
7     <s:property value="[1].studentName" />
8     <br> 姓名5:${requestScope.studentName}    
 1 public class HelloWorldAction extends ActionSupport {
 2     /**
 3      * 
 4      */
 5     private static final long serialVersionUID = -7840227232203094654L;
 6     private String studentName;
 7 
 8     public String getStudentName() {
 9         return studentName;
10     }
11 
12     public void setStudentName(String studentName) {
13         this.studentName = studentName;
14     }
15 
16     private String password;
17 
18     public String execute() {
19         System.out.println("execute.....");
20         System.out.println("studentName:" + studentName);
21         System.out.println("password:" + password);
22         // ValueStack vs=ActionContext.getContext().getValueStack();
23         ActionContext context = ActionContext.getContext();
24         ValueStack vs = context.getValueStack();
25         // 值栈的栈顶
26         Student student = new Student("111111");
27         vs.push(student);
28         return "info";
29     }
30 
31     public String getPassword() {
32         return password;
33     }
34 
35     public void setPassword(String password) {
36         this.password = password;
37     }
38 }
 1 public class Student {
 2     private String studentName;
 3 
 4     public Student(String studentName) {
 5         this.studentName = studentName;
 6     }
 7 
 8     public String getStudentName() {
 9         return studentName;
10     }
11 //
12     public void setStudentName(String studentName) {
13         this.studentName = studentName;
14     }
15 }

图片

原文地址:https://www.cnblogs.com/ydymz/p/6443893.html