struts1.X总结(10-20)

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//结构

Group group = new Group();

group.setName("机电职业技术学院");

User user = new User();

user.setUsername("张三");

user.setAge(18);

user.setGroup(group);

request.setAttribute("user", user);

//map

Map mapValue = new HashMap();

mapValue.put("key1", "value1");

mapValue.put("key2", "value2");

request.setAttribute("mapvalue", mapValue);

//字符串数组

String[] strArray = new String[]{"a", "b", "c"};

request.setAttribute("strarray", strArray);

User[] users = new User[10];

for (int i=0; i<10; i++) {

User u = new User();

u.setUsername("U_" + i);

users[i] = u;

}

request.setAttribute("users", users);

List userList = new ArrayList();

for (int i=0; i<10; i++) {

User uu = new User();

uu.setUsername("UU_" + i);

userList.add(uu);

}

request.setAttribute("userlist", userList);

//empty

request.setAttribute("value1", null);

request.setAttribute("value2", "");

request.setAttribute("value3", new ArrayList());

request.setAttribute("value4", "123456");

return mapping.findForward("success");

客户端

<h1>测试EL表达式</h1>

<hr>

<li>普通字符串</li>

hello(jsp脚本):<%=request.getAttribute("hello") %>

hello(el表达式,el表达式的使用方法$和{}):${hello }

hello(el表达式,el的隐含对象pageScope,requestScope,sessionScope,applicationScope, 如果未指定scope,它的搜索顺序为pageScope~applicationScope):${requestScope.hello }

hello(el表达式,scope=session):${sessionScope.hello }

<li>结构,采用.进行导航，也称存取器</li>

姓名：${user.username }

年龄：${user.age }

所属组：${user.group.name }

<li>输出map,采用.进行导航，也称存取器</li>

mapvalue.key1:${mapvalue.key1 }

mapvalue.key2:${mapvalue.key2 }

strarray[2]:${strarray[1] }

<li>输出对象数组,采用[]和下标</li>

userarray[3].username:${users[2].username }

<li>输出list,采用[]和下标</li>

userlist[5].username:${userlist[4].username }

<li>el表达式对运算符的支持</li>

1+2=${1+2 }

10/5=${10/5 }

10 div 5=${10 div 5 }

10%3=${10 % 3 }

10 mod 3=${10 mod 3 }

<!--

==/eq

!=/ne

</lt

>/gt

<=/le

>=/ge

&&/and

||/or

!/not

//div

%/mod

-->

<li>测试empty</li>

value1:${empty value1 }

value2:${empty value2 }

value3:${empty value3 }

value4:${empty value4 }

value4:${!empty value4 }

JSTL核心库标签

Jstl.jar是接口

Standard.jar是实现

页面加入<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>

普通属性和文本的使用

服务器

//普通属性

request.setAttribute("hello", "Hello World");

//html文本

request.setAttribute("bj", "北京欢迎您");

客户端

<h1>测试jstl核心库</h1>

<hr>

hello(default):<c:out value="${hello}"/>

hello(el表达式):${hello }

hello(default="123"):<c:out value="${abc}" default="123"/>

//等同于

hello(default="123"):<c:out value="${abc}">123</c:out>

bj(defalut):<c:out value="${bj}"/>

bj(escapeXml="true"):<c:out value="${bj}" escapeXml="true"/>

bj(escapeXml="false"):<c:out value="${bj}" escapeXml="false"/>

//等同于

bj(el表达式):${bj }

<li>测试c:set和c:remove</li>

<c:set value="123" var="temp"/>//默认是在page页面有效

temp:${temp }

<c:remove var="temp"/>

temp:${temp }

条件分支

服务器

//测试条件控制标签

request.setAttribute("v1", 1);

request.setAttribute("v2", 2);

request.setAttribute("v3", new ArrayList());

request.setAttribute("v4", "test");

客户端

<li>测试条件控制标签c:if</li>

<c:if test="${v1 lt v2}" var="v">

v1小于v2 v=${v }

</c:if>

<c:if test="${empty v3}">

v3为空

</c:if>

<c:if test="${empty v4}">

v4为空

</c:if>

<li>测试条件控制标签c:choose,c:when,c:otherwise</li>

<c:choose>

<c:when test="${v1 lt v2}">

v1小于v2

</c:when>

<c:otherwise>

v1大于v2

</c:otherwise>

</c:choose>

<c:choose>

<c:when test="${empty v4}">

v4为空

</c:when>

<c:otherwise>

v4不为空

</c:otherwise>

</c:choose>

循环控制标签

服务器

//测试c:forEach

Group group = new Group();

group.setName("机电职业技术学院");

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);

//测试循环输出map

Map map = new HashMap();

map.put("k1", "v1");

map.put("k2", "v2");

request.setAttribute("mapvalue", map);

客户端

<li>测试循环控制标签c:forEach</li>

<tr>

</tr>

<c:choose>

<c:when test="${empty userlist}">

<tr>

<td colspan="3">没有符合条件的数据!</td>

</tr>

</c:when>

<c:otherwise>

<c:forEach items="${userlist}" var="u">

<tr>

<td>${u.username }</td>

<td>${u.group.name }</td>

</tr>

</c:forEach>

</c:otherwise>

</c:choose>

</table>

<li>测试循环控制标签c:forEach,varstatus</li>

<tr>

</tr>

<c:choose>

<c:when test="${empty userlist}">

<tr>

<td colspan="3">没有符合条件的数据!</td>

</tr>

</c:when>

<c:otherwise>

<c:forEach items="${userlist}" var="user" varStatus="vs">

<c:choose>

<c:when test="${vs.count % 2 == 0}">

</c:when>

<c:otherwise>

<tr>

</c:otherwise>

</c:choose>

<td>

<c:out value="${user.username}"/>

</td>

<td>

<c:out value="${user.age}"/>

</td>

<td>

<c:out value="${user.group.name}"/>

</td>

</tr>

</c:forEach>

</c:otherwise>

</c:choose>

</table>

<li>测试循环控制标签c:forEach,begin,end,step</li>

<tr>

</tr>

<c:choose>

<c:when test="${empty userlist}">

<tr>

<td colspan="3">没有符合条件的数据!</td>

</tr>

</c:when>

<c:otherwise>

<c:forEach items="${userlist}" var="user" begin="2" end="8" step="2">

<tr>

<td>${user.username}</td>

<td>${user.group.name }</td>

</tr>

</c:forEach>

</c:otherwise>

</c:choose>

</table>

<li>测试循环控制标签c:forEach，普通循环</li>

<c:forEach begin="1" end="10">

a

</c:forEach>

<li>测试循环控制标签c:forEach，输出map</li>

<c:forEach items="${mapvalue}" var="v">

${v.key }=${v.value }

</c:forEach>

forTokens标签逗号表达式

服务器

//测试c:forTokens

request.setAttribute("strTokens", "1,2,3,4,5,6");

客户端

<li>测试循环控制标签c:forTokens</li>

<c:forTokens items="${strTokens}" delims="," var="v">

${v }

</c:forTokens>

<li>测试c:catch</li>

try {

Integer.parseInt("asdfsdf");

}catch(Exception e) {

out.println(e.getMessage());

}

<c:catch var="exinfo">

Integer.parseInt("asdfsdf");

</c:catch>

${exinfo }

<li>测试c:import</li> //相当于include

<c:import url="http://localhost:8080/struts_login"/>

<li>测试c:url和c:param</li>

<c:url value="http://localhost:8080/drp/sysmgr/user_add.jsp" var="v">

<c:param name="username" value="Jack"/>

<c:param name="age" value="20"/>

</c:url>

${v }

<li>测试:redirect</li>

//代替上面的url属于相对路径

<c:redirect context="/struts_login" url="/index.jsp"/>

格式化标签库

格式化日期

服务器端

request.setAttribute("today", new Date());

客户端

<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt"%>

<h1>测试jstl格式化库</h1>

<hr>

<li>测试日期的格式化</li>

today(default):<fmt:formatDate value="${today}"/>

today(type="date"):<fmt:formatDate value="${today}" type="date"/>

today(type="time"):<fmt:formatDate value="${today}" type="time"/>

today(type="both"):<fmt:formatDate value="${today}" type="both"/>

today(dateStyle="short"):<fmt:formatDate value="${today}" dateStyle="short"/>

today(dateStyle="medium"):<fmt:formatDate value="${today}" dateStyle="medium"/>

today(dateStyle="long"):<fmt:formatDate value="${today}" dateStyle="long"/>

today(dateStyle="full"):<fmt:formatDate value="${today}" dateStyle="full"/>

today(pattern="yyyy/MM/dd HH:mm:ss"):<fmt:formatDate value="${today}" pattern="yyyy/MM/dd HH:mm:ss"/>

today(pattern="yyyy/MM/dd HH:mm:ss"):<fmt:formatDate value="${today}" pattern="yyyy/MM/dd HH:mm:ss" var="d"/>

${d }

格式化数字

服务器

request.setAttribute("n", 123456.123);

request.setAttribute("p", 0.12345);

客户端

<li>测试数字的格式化</li>

n(default):<fmt:formatNumber value="${n}"/>

n(pattern="###,###.##"):<fmt:formatNumber value="${n}" pattern="###,###.##"/>

n(pattern="###,###.0000"):<fmt:formatNumber value="${n}" pattern="###,###.0000"/>

n(groupingUsed="false"):<fmt:formatNumber value="${n}" groupingUsed="false"/>

n(minIntegerDigits="10"):<fmt:formatNumber value="${n}" minIntegerDigits="10"/>

n(type="currency"):<fmt:formatNumber value="${n}" type="currency"/>

n(type="currency"):<fmt:formatNumber value="${n}" type="currency" currencySymbol="$"/>

n(type="percent"):<fmt:formatNumber value="${p}" type="percent" maxFractionDigits="2" minFractionDigits="2"/>

函数库的使用

服务器端

request.setAttribute("hello", "hello world");

List list = new ArrayList();

list.add("t1");

list.add("t2");

request.setAttribute("list", list);

客户端//参看jstl-1—1-mr2-spec.pdf

<%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions"%>

<h1>测试jstl函数库</h1>

<hr>

hello.length=(jsp脚本):<%=((String)request.getAttribute("hello")).length() %>

hello.length(jstl函数库，函数调用必须在el表达式中前缀+冒号+函数名):${fn:length(hello) }

list.length:${fn:length(list) }

自定义函数库