El表达式判断是否为空字符串spa
${empty 值} 返回true ,表示为空字符串;字符串
<c:if test=" ${empty basicTree.phone} ">it
<td>wwww </td>class
</c:if>test
El表达式判断是否为空gc
${值 eq null } 返回true 的话，表示为空di
<c:if test="${basicTree.phone eq null }">co
<td>mmmm</td>字符
</c:if>
双保险判断不为空
<c:if test="${not empty basicTree.phone && !(basicTree.phone eq null) }">
哈哈 </c:if>