1:我有一个包含多个 html“TR”的 JSP
<tr>'s
我的页面
<% ...%>
<html>
...
<body>
<table>
<tr class="1"> This is first line</tr>
<br/>
<tr class="2"> This is Second line</tr>
<br/>
<tr class="3"> This is Third line</tr>
<br/>
<tr class="4"> This is Fourth line</tr>
<br/>
<tr class="5"> This is Fifth line</tr>
<br/>
...
</html>
2:现在我正在获取用户 session (如果已登录)。注意>>:使用Liferay主题显示在此处
<%String userEmail=themeDisplay.getUser().getEmailAddress();%>
<c:set var="userEmail" value="<%=userEmail%>"></c:set>
3:我检查了其是否是访客或注册/登录用户。
然后，第一个和最后一个“TR”的显示将更改为登录用户。
<% ...%>
<html>
...
<body>
<table>
<c:if test="${not empty userEmail}">
<tr class="1"> This is first line for registered user</tr>
<c:if test="${empty userEmail}">
<tr class="1"> This is first line</tr>
<br/>
<tr class="2"> This is Second line</tr>
<br/>
<tr class="3"> This is Third line</tr>
<br/>
<tr class="4"> This is Fourth line</tr>
<br/>
<c:if test="${not empty userEmail}">
<tr class="5"> This is Fifth line for registered user</tr>
<c:if test="${empty userEmail}">
<tr class="5"> This is Fifth line</tr>
<br/>
...
</html>
这工作正常!!
我的问题>>>>>如果我想将此检查作为某种常量，这不会在 JSP/HTML 页面上重复多次。该怎么办？？？
<c:if> //to be declared only once. And called which ever <TR> needs a check??
最佳答案
一些替代方案:
- 使用
c:set在页面上设置注册变量，用于c:choose。
<c:set var="registered" value="${not empty userEmail}"/>
<c:choose>
<c:when test="${registered}">
<tr class="1"> This is first line for registered user</tr>
</c:when>
<c:otherwise>
<tr class="1"> This is first line</tr>
</c:otherwise>
</c:choose>
- Write the first and last lines as blank table rows, then use a
c:chooseto run javascript to insert the data you want.
<table>
<tr id="firstRow"></tr>
...
<tr id="lastRow"></tr>
</table>
<c:choose>
<c:when test="${not empty userEmail}">
<script>
document.getElementById('firstRow').innerHTML = 'This is first line for registered user';
document.getElementById('lastRow').innerHTML = 'This is Fifth line for registered user';
</script>
</c:when>
<c:otherwise>
<script>
document.getElementById('firstRow').innerHTML = 'This is first line';
document.getElementById('lastRow').innerHTML = 'This is Fifth line';
</script>
</c:otherwise>
</c:choose>
关于java - <C :if/Choose/When> condition to be made as one 的多个实例，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/4794195/