struts2 ognl表达式#和%的使用
2018-05-18 本文已影响0人
DouDouZH
一、#的使用
1、获取contex里面的数据
2、演示#操作
（1）步骤
- 向request放值
- 用ognl获取
- 获取context 里的数据，写ognl的时候添加#context的key名称.域对象名称
（2）代码
ValuesStackAction5.java
package work.zhangdoudou.Action;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import org.apache.struts2.ServletActionContext;
import com.opensymphony.xwork2.ActionSupport;
import work.zhangdoudou.Bean.User;
public class ValuesStackAction5 extends ActionSupport{
@Override
public String execute() throws Exception {
HttpServletRequest request=ServletActionContext.getRequest();
request.setAttribute("name", "zhangsan");
return SUCCESS;
}
}
struts.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
"http://struts.apache.org/dtds/struts-2.3.dtd">
<struts>
<constant name="struts.enable.DynamicMethodInvocation" value="false" />
<constant name="struts.devMode" value="true" />
<package name="default" namespace="/" extends="struts-default">
<action name="userAction5" class="work.zhangdoudou.Action.ValuesStackAction5" method="execute">
<result name="success">/ValuesStack.jsp</result>
</action>
</package>
</struts>
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
<display-name>struts2_ognl</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<filter>
<filter-name>struts2</filter-name>
<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
</web-app>
ValuesStack.jsp页面
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="/struts-tags" prefix="s" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>My JSP 'ValuesStackAction.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<s:debug></s:debug>
<!-- 获取context 里的数据，写ognl的时候添加#context的key名称.域对象名称 -->
<s:property value="#request.name"/>
</body>
</html>
（3）运行效果
image.png
二、%的使用
1、在struts2标签中表单标签
（1）在struts2标签里面使用ognl表达式，如果直接在struts表单里使用ognl表达式不能识别，只有加%才能识别
（2）代码
ValuesStackAction5.java
package work.zhangdoudou.Action;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import org.apache.struts2.ServletActionContext;
import com.opensymphony.xwork2.ActionSupport;
import work.zhangdoudou.Bean.User;
public class ValuesStackAction5 extends ActionSupport{
@Override
public String execute() throws Exception {
HttpServletRequest request=ServletActionContext.getRequest();
request.setAttribute("name", "zhangsan");
return SUCCESS;
}
}
struts.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
"http://struts.apache.org/dtds/struts-2.3.dtd">
<struts>
<constant name="struts.enable.DynamicMethodInvocation" value="false" />
<constant name="struts.devMode" value="true" />
<package name="default" namespace="/" extends="struts-default">
<action name="userAction5" class="work.zhangdoudou.Action.ValuesStackAction5" method="execute">
<result name="success">/ValuesStack.jsp</result>
</action>
</package>
</struts>
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
<display-name>struts2_ognl</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<filter>
<filter-name>struts2</filter-name>
<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
</web-app>
ValuesStack.jsp页面
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="/struts-tags" prefix="s" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>My JSP 'ValuesStackAction.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<s:debug></s:debug>
<hr>
ognl%的使用<br>
username<s:textfield name="username" value="%{#request.name}"></s:textfield>
</body>
</html>
（3）效果
image.png
