jsp判断List长度
浏览数：25 /
时间：2015年06月09日
大家好：
今天遇到的一个问题就是后台往前台传List ，前台判断List的长度！
查别人的都说要加别的标签
<span style="font-size:14px;color:#cc0000;">jsp开发中经常要判断list或者字符串的长度来做些事情，因为jstl标签中的if不支持else，所以选择while来做。
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/functions" prefix="fn"%>--------这里就需要有standard.jar这个包
引入两个标签库之后就能实现长度判断了，例如
Jsp代码 收藏代码
<c:choose>
<c:when test="${fn:length(contact.tagschosen) == 0}">
<span class="grouped">未分组</span>
</c:when>
<c:otherwise>
<c:forEach items="${contact.tagschosen}" var="tags">
<span class="grouped">${tags.tagname}</span>
</c:forEach>
</c:otherwise>
</c:choose> </span>而我今天要说的是只需要 <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%> 这个标签就好了
只需要在 body中加入个隐式标签就可以轻轻松松判断了
<input type="hidden" name="tcMedicineList" value="${tcMedicineList}" />
<c:if test="${tcMedicineList.size()>2}">
这样就OK了！！！
<span style="font-size:14px;"><body>
<input type="hidden" name="tcMedicineList" value="${tcMedicineList}" />
<input type="hidden" name="weMedicineList" value="${weMedicineList}" />
<input type="hidden" name="otMedicineList" value="${otMedicineList}" />
<input type="hidden" name="trMedicineList" value="${trMedicineList}" />
<input type="hidden" name="ptcMedicineList" value="${ptcMedicineList}" />
<!--recipe start-->
<div class="container">
<dl class="recipe_pay_detail recipe_detail">
<dt class="medicine_head"><i class="ico ico_recipe recipe_bg6"></i>中药药品：</dt>
<dd id="medicine_info_chn">
</span><span style="font-size:18px;color:#ff6600;"> <span style="background-color: rgb(102, 0, 204);"><c:forEach items="${tcMedicineList}" var="tcMedicineList" begin="0" end="1"></span></span><span style="color: rgb(255, 102, 0);font-size:18px; font-family: Arial, Helvetica, sans-serif;"> </span><span style="color: rgb(255, 102, 0);font-size:18px; font-family: Arial, Helvetica, sans-serif;"><!-- 循环List只显示前两条 --></span><span style="font-size:14px;"> <p><span>${tcMedicineList.name}</span>${tcMedicineList.standard} </p>
</c:forEach>
</span><strong style="font-size:14px;"> </strong><span style="font-size:18px;"> </span><span style="color:#ff9900;"><span style="font-size:18px;"><span style="background-color: rgb(51, 102, 255);"> <c:if test="${tcMedicineList.size()!=0&&2>tcMedicineList.size()}"></span> </span><span style="font-size:14px;"> </span></span><span style="color: rgb(255, 102, 0); font-size: 18px; font-family: Arial, Helvetica, sans-serif;"><!-- 如果List条数不等于0 并且条数小于2条时 --></span><span style="font-size:14px;"><span style="color:#ff9900;">
</span>
<c:forEach items="${ptcMedicineList}" var="ptcMedicineList"<span style="background-color: rgb(51, 102, 255);"><span style="color:#ff0000;"> begin="0" end="0"</span></span>>
<p>
剂量：${ptcMedicineList.num} ${ptcMedicineList.unit}<br/>
<%-- 剂量：${ptcMedicineList.dosage}<br> --%>
用法：${ptcMedicineList.usemethod} ${ptcMedicineList.dosage}
</p>
</c:forEach>
</c:if>
<c:if test="${tcMedicineList.size()>2}"> </span><span style="color: rgb(255, 102, 0); font-family: Arial, Helvetica, sans-serif; font-size: 18px;"><!-- 如果List条数大于2条时 --></span><span style="font-size:14px;">
<c:forEach items="${ptcMedicineList}" var="ptcMedicineList" <span style="background-color: rgb(51, 102, 255);"><span style="color:#ff6600;">begin="0" end="0"></span></span><span style="color:#ffff66;">></span> </span><span style="color: rgb(255, 102, 0); font-family: Arial, Helvetica, sans-serif;font-size:18px;"><!-- 循环List只显示前一条 --></span><span style="font-size:14px;">
<p>
剂量：${ptcMedicineList.num} ${ptcMedicineList.unit}<br/>
用法：${ptcMedicineList.usemethod} ${ptcMedicineList.dosage}
<a href="#" class="btn btn_o_c btn_open" id="btn_open_chn">展开</a>
</p>
</c:forEach>
</c:if>
</dd>
<dd id="medicine_detail_chn">
<c:forEach items="${tcMedicineList}" var="tcMedicineList">
<p> <span>${tcMedicineList.name}</span>${tcMedicineList.standard}</p>
</c:forEach>
<c:forEach items="${ptcMedicineList}" var="ptcMedicineList" begin="0" end="0"></span><span style="color: rgb(255, 102, 0); font-family: Arial, Helvetica, sans-serif;font-size:18px;"><!-- 循环List只显示前一条 --></span><span style="font-size:14px;">
<p>
剂量：${ptcMedicineList.num} ${ptcMedicineList.unit}<br/>
用法：${ptcMedicineList.usemethod} ${ptcMedicineList.dosage}
<a href="#" class="btn btn_o_c btn_close" id="btn_close_chn">收起</a>
</p>
</c:forEach>
</dd>
<dt class="medicine_head"><i class="ico ico_recipe recipe_bg4"></i>西药药品：</dt>
<dd id="medicine_info">
<c:forEach items="${weMedicineList}" var="weMedicineList" begin="0" end="1">
<p><span>${weMedicineList.name}</span>${weMedicineList.standard}</p>
</c:forEach>
<c:if test="${weMedicineList.size()>2}">
<p>...<a href="#" class="btn btn_o_c btn_open" id="btn_open">展开</a></p>
</c:if>
</dd>
<dd id="medicine_detail">
<c:forEach items="${weMedicineList}" var="weMedicineList">
<p><span>${weMedicineList.name}</span>${weMedicineList.standard}</p>
</c:forEach>
<p> <a href="#" class="btn btn_o_c btn_close" id="btn_close">收起</a></p>
</dd>
<%--
<dt> <i class="ico ico_recipe recipe_bg4"></i>检查项目：</dt>
<dd id="medicine_info_check">
<c:forEach items="${entity}" var="entity" begin="0" end="1">
<p><span>${entity.name}</span></p>
</c:forEach>
<p><a href="#" class="btn btn_o_c btn_open" id="btn_open">展开</a></p>
</dd>
<dd id="medicine_detail_check">
<c:forEach items="${entity}" var="entity">
<p><span>${entity.name}</span></p>
</c:forEach>
<p> <a href="#" class="btn btn_o_c btn_close" id="btn_close">收起</a></p>
</dd>
--%>
<dt><i class="ico ico_recipe recipe_bg5"></i>其他：</dt>
<dd>
<c:forEach items="${otMedicineList}" var="otMedicineList">
<p><span>${otMedicineList.name}</span>${otMedicineList.standard}</p>
</c:forEach>
</dd>
<dt><i class="ico ico_recipe recipe_bg2"></i>治疗项目：</dt>
<c:forEach items="${trMedicineList}" var="trMedicineList">
<dd><p><span>${trMedicineList.name}</span>${trMedicineList.standard}</p></dd>
</c:forEach>
<dd class="recipe_sum sum_all">合计：${fee} 元</dd>
</dl>
</div></span>
郑重声明：本站内容如果来自互联网及其他传播媒体，其版权均属原媒体及文章作者所有。转载目的在于传递更多信息及用于网络分享，并不代表本站赞同其观点和对其真实性负责，也不构成任何其他建议。
