strruts标签使用简介

来源：互联网发布：申请域名和空间编辑：程序博客网时间：2024/06/06 03:42

web.xml配置如下：

Xml代码

<filter>
<filter-name>struts2</filter-name>
<filter-class>
org.apache.struts2.dispatcher.FilterDispatcher
</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>

<filter><filter-name>struts2</filter-name><filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class></filter><filter-mapping><filter-name>struts2</filter-name><url-pattern>/*</url-pattern></filter-mapping>

struts.xml配置如下：

Xml代码

<package name="tags" extends="struts-default">
<action name="tags" class="com.mengya.action.TagsAction">
<result name="success">/tags.jsp</result>
</action>
</package>

<package name="tags" extends="struts-default"><action name="tags" class="com.mengya.action.TagsAction"><result name="success">/tags.jsp</result></action></package>

TagsAction如下：

Java代码

public class TagsAction extends ActionSupport {
private String username;
private String password;
@Override
public String execute() throws Exception {
this.addFieldError("actionError", "error!!");
return SUCCESS;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
}

public class TagsAction extends ActionSupport {private String username;private String password;@Overridepublic String execute() throws Exception {this.addFieldError("actionError", "error!!");return SUCCESS;}public String getPassword() {return password;}public void setPassword(String password) {this.password = password;}public String getUsername() {return username;}public void setUsername(String username) {this.username = username;}}

Dog Bean如下：

Java代码

public class Dog {
private String dogName;
public String getDogName() {
return dogName;
}
public void setDogName(String dogName) {
this.dogName = dogName;
}
@Override
public String toString() {
return "Dog：DogName=" + dogName;
}
}

public class Dog {private String dogName;public String getDogName() {return dogName;}public void setDogName(String dogName) {this.dogName = dogName;}@Overridepublic String toString() {return "Dog：DogName=" + dogName;}}

页面struts标签使用如下：

Html代码

<a href="tags.action?username=u&password=p&age=9">Struts2Tags</a>
<body>
<ol>
<li>
property：
<s:property value="username" />
</li>
<li>
property 取值为字符串：
<s:property value="'username'" />
</li>
<li>
property 设定为默认值：
<s:property value="admin" default="管理员" />
</li>
<li>
property 设定为HTML：
<s:property value="'<hr/>'" escape="false" />
</li>
<hr />
<li>
set 设定mengya的值（默认为Request和ActionContext）：
<s:set var="mengya" value="username"></s:set>
</li>
<li>
set 从request中取值：
<s:property value="#request.mengya" />
</li>
<li>
set 从ActionContext中取值：
<s:property value="#mengya" />
</li>
<li>
set 设定范围：
<s:set var="adminPassword" value="password" scope="session" />
</li>
<li>
set 从相应的范围取值：
<%=session.getAttribute("adminPassword")%>
</li>
<li>
set 从相应的范围取值：
<s:property value="#session.adminPassword" />
</li>
<hr>
<li>
bean 定义bean，并使用bean的param来设定的新属性值
<s:bean name="com.mengya.bean.Dog"></s:bean>
<%-- 没有指定var则在</s:bean>之前会构造一个对象放在椎顶在</s:bean>结束之前则放到了actionContext中 --%>
</li>
<li>
bean 定义bean，并使用bean的param来设定的新属性值
<s:bean name="com.mengya.bean.Dog" var="myDog">
<s:param name="dogName" value="'myDog'"></s:param>
</s:bean>
取出值：
<s:property value="#myDog" />
</li>
<hr>
<li>
include 包含静态英文html
<s:include value="/include1.html"></s:include>
</li>
<li>
include 包含静态中文html
<s:include value="/include2.html"></s:include>
</li>
<li>
%的用法：%是将%{}中的内空强转成ognl表达示而不是普通字符串
<s:set var="incPage" value="'/include1.html'"></s:set>
<s:include value="incPage"></s:include>
<s:include value="%{incPage}"></s:include>
<%-- 将incPage作为ognl表达式 --%>
</li>
<li>
fielderror：
<s:fielderror key="actionError" theme="simple"></s:fielderror>
</li>
<hr>
<li>
if elseif else: age =
<s:property value="#parameters.age[0]" />
<s:if test="#parameters.age[0]<0">
age error!
</s:if>
<s:elseif test="#parameters.age[0]<20">
to young!
</s:elseif>
<s:else>
OK!
</s:else>
  |  
<s:set var="age" value="#parameters.age[0]"></s:set>
<s:if test="age<0">
age error!
</s:if>
<s:elseif test="age<20">
to young!
</s:elseif>
<s:else>
ok!
</s:else>
  |  
<s:if test="#parameters.aaa==null">null</s:if>
</li>
<li>
遍历集合：
<s:iterator value="{'aa','bb','cc'}">
<s:property /> |
</s:iterator>
</li>
<li>
自定义变量：
<s:iterator value="{'aa','bb','cc'}" var="temp">
<s:property value="#temp" /> | <s:property
value="#temp.toUpperCase()" />
</s:iterator>
</li>
<li>
使用status:
<s:iterator value="{11,22,33}" status="status">
<s:property /> |遍历过的总元素：<s:property value="#status.count" /> |当前元素索引：<s:property
value="#status.index" /> |当前值是否为偶数：<s:property
value="#status.even" /> |当前值是否为奇数：<s:property
value="#status.odd" /> |当前值是否为第一个：<s:property
value="#status.first" /> |当前值是否为最后一个：<s:property
value="#status.last" />
</s:iterator>
</li>
<s:debug></s:debug>
</ol>
总结：
$用于i18n和struts配置文件
#用于得到ActionContext的值
%将原本的文本属性解析为OGNL表达式，对于本来就是OGNL的属性不起做用
</body>