Struts1_学习笔记3_struts0300_taglib_bean_logic_Iterate标签

bean标签：

Action:

public ActionForward execute(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
		// 普通属性
		request.setAttribute("hello", "Hello World");
		// html文本
		request.setAttribute("hz", "<font color='red'>杭州欢迎您</font>");
		// 日期
		request.setAttribute("today", new Date());
		// 数字
		request.setAttribute("n", 123456.987);
		// 结构
		Group group = new Group();
		group.setName("和盈");
		User user = new User();
		user.setUsername("张三");
		user.setAge(18);
		user.setGroup(group);
		request.setAttribute("user", user);

		return mapping.findForward("success");
	}

页面显示：

<h1>测试BeanWrite</h1>
	<hr>
	<li>普通字符串</li><br>
	hello(jsp脚本):<%=request.getAttribute("hello") %><br>
	hello(标签):<bean:write name="hello"/><br>
	<p>
	<li>html文本</li><br>
	hz(default):<bean:write name="hz"/><br>
	hz(filter="true"):<bean:write name="hz" filter="true"/><br>
	hz(filter="false"):<bean:write name="hz" filter="false"/><br>
	<p>
	<li>格式化日期</li><br>
	today(default):<bean:write name="today"/><br>
	today(format="yyyy-MM-dd HH:mm:ss"):<bean:write name="today" format="yyyy-MM-dd HH:mm:ss"/>
	<p>
	<li>格式化数字</li><br>
	n(default):<bean:write name="n"/><br>
	n(format="###,###.####"):<bean:write name="n" format="###,###.####"/><br>
	n(format="###,###.####"):<bean:write name="n" format="###,###.0000"/><br>
	<p>
	<li>结构</li><br>
	姓名：<input type="text" value="<bean:write name="user" property="username"/>"><br>
	年龄：<input type="text" value="<bean:write name="user" property="age"/>"><br>
	所属组：<input type="text" value="<bean:write name="user" property="group.name"/>"><br>
	</body>

配置文件：

<action-mappings>
		<action path="/beanwrite" type="com.aowin.struts.BeanWriteTestAction">
			<forward name="success" path="/beanwrite.jsp" />
		</action>

		<action path="/emptypresent" type="com.aowin.struts.EmptyPresentTestAction">
			<forward name="success" path="/emptypresent.jsp" />
		</action>

		<action path="/iterate" type="com.aowin.struts.IterateTestAction">
			<forward name="success" path="/iterate.jsp" />
		</action>
	</action-mappings>

	<message-resources parameter="MessageResources" />

使用struts1 bean:write标签必须提供一份国际化文件： MessageResources
否则会报：
Cannot find message resources under key org.apache.struts.action.MESSAGE
在src下面提供一份文件即可 内容为空也可以


使用bean标签需要在页面中加入：

<%@ taglib prefix="bean" uri="http://struts.apache.org/tags-bean"%>   

logic标签：
Action:

@Override
	public ActionForward execute(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
		request.setAttribute("attr1", null);
		request.setAttribute("attr2", "");
		request.setAttribute("attr3", new ArrayList());
		return mapping.findForward("success");
	}

页面使用标签：

<h1>测试empty,notEmpty,present,notPresent</h1>
	<hr>
	<logic:empty name="attr1">
		attr1为空<br>
	</logic:empty>
	<logic:notEmpty name="attr1">
		attr1不为空<br>
	</logic:notEmpty>
	<logic:present name="attr1">
		attr1存在<br>
	</logic:present>
	<logic:notPresent name="attr1">
		attr1不存在<br>
	</logic:notPresent>
	
	<p>
	<logic:empty name="attr2">
		attr2为空<br>
	</logic:empty>
	<logic:notEmpty name="attr2">
		attr2不为空<br>
	</logic:notEmpty>
	<logic:present name="attr2">
		attr2存在<br>
	</logic:present>
	<logic:notPresent name="attr2">
		attr2不存在<br>
	</logic:notPresent>
	
	<p>
	<logic:empty name="attr3">
		attr3为空<br>
	</logic:empty>
	<logic:notEmpty name="attr3">
		attr3不为空<br>
	</logic:notEmpty>
	<logic:present name="attr3">
		attr3存在<br>
	</logic:present>
	<logic:notPresent name="attr3">
		attr3不存在<br>
	</logic:notPresent>

Iterate标签：

public ActionForward execute(ActionMapping mapping, ActionForm form,
			HttpServletRequest request, HttpServletResponse response)
			throws Exception {
		Group group = new Group();
		group.setName("和盈");
		
		List userList = new ArrayList();
		for (int i=0; i<10; i++) {
			User user = new User();
			user.setUsername("user_" + i);
			user.setAge(18+i);
			user.setGroup(group);
			userList.add(user);
		}
		
		request.setAttribute("userlist", userList);
		
		return mapping.findForward("success");
	}

页面显示：

<h1>测试Iterate</h1>
	<hr>
	<li>jsp脚本</li><br>
	<table border="1">  
		<tr>
			<td>姓名</td>
			<td>年龄</td>
			<td>所属组</td>
		</tr>
		<%
			List userList = (List)request.getAttribute("userlist");
			if (userList == null || userList.size() == 0) {
		%>
			<tr>
				<td colspan="3">没有符合条件的数据!</td>
			</tr>
		<%
			}else {
				for (Iterator iter=userList.iterator(); iter.hasNext(); ) {
					User user = (User)iter.next();
		%>
			<tr>
				<td><%=user.getUsername() %></td>
				<td><%=user.getAge() %></td>
				<td><%=user.getGroup().getName() %></td>
			</tr>
		<%
				}
			}
		%>
	</table>
	
	<p>
	<li>标签</li><br>
	<table border="1">
		<tr>
			<td>姓名</td>
			<td>年龄</td>
			<td>所属组</td>
		</tr>
		<logic:empty name="userlist">
			<tr>
				<td colspan="3">没有符合条件的数据!</td>
			</tr>
		</logic:empty>
		<logic:notEmpty name="userlist">
			<logic:iterate id="u" name="userlist">
				<tr>
					<td>
						<bean:write name="u" property="username"/>
					</td>
					<td>
						<bean:write name="u" property="age"/>
					</td>
					<td>
						<bean:write name="u" property="group.name"/>
					</td>
				</tr>
			</logic:iterate>
		</logic:notEmpty>
	</table>	

使用Iterate标签加上：

<%@ taglib prefix="bean" uri="http://struts.apache.org/tags-bean"%>    
<%@ taglib prefix="logic" uri="http://struts.apache.org/tags-logic"%>