settagaction.java
package com.h3.common.action;
import com.opensymphony.xwork2.actionsupport;
public class settagaction extends actionsupport{
private string msg = "struts 2 is a funny framework";
public string getmsg() {
return msg;
}
public string execute() throws exception {
return success;
}
}
set.jsp
<%@ taglib prefix="s" uri="/struts-tags" %>
<html>
<head><title>www.h3.com</title>
</head>
<body>
<h1>struts 2 set tag example</h1>
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</div></div><h2>1. <s:set var="varmsg" value="msg" /></h2>
<s:set var="varmsg" value="msg" />
<s:property value="varmsg" />
<h2>2. <s:set var="varurl" value="%{'http://www.h3.com'}" /></h2>
<s:set var="varurl" value="%{'http://www.h3.com'}" />
<s:property value="varurl" />
</body>
</html>
它是如何工作的？
1. <s:set var=”varmsg” value=”msg” />
调用动作的 getmsg()方法返回的值赋给变量名为 “varmsg“.
2. <s:set var=”varurl” value=”%{‘http://www.h3.com’}” />
硬编码字符串，并将其分配给一个名为变量 “varurl“.
例如,
public class settagaction extends actionsupport{
private string msg;
public string setmsg(string msg) {
this.msg = msg;
}
...
<s:set var="msg" value="%{'this is a message'}" />
这是错误的，<s:set>标签将不会调用setmsg()方法，它只会以名为“msg”分配“value”到变量。没有动作属性值。
<?xml version="1.0" encoding="utf-8" ?> <!doctype struts public "-//apache software foundation//dtd struts configuration 2.0//en" "http://struts.apache.org/dtds/struts-2.0.dtd"> <struts> <constant name="struts.devmode" value="true" /> <package name="default" namespace="/" extends="struts-default"> <action name="settagaction" class="com.h3.common.action.settagaction" > <result name="success">pages/set.jsp</result> </action> </package> </struts>
http://localhost:8080/struts2settag/settagaction.action
在浏览器中打开上面的网址，输出结果如下：
代码下载 - http://pan.baidu.com/s/1mgs6tle
