The select drop-down box of dwz is not empty to judge
1，class="required combox"
2, when it is not selected, value="", cannot have a value, otherwise it cannot be judged to be empty, and "" is empty
<p>
<label>Initiator Package:</label>
<select class="required combox" name="wtfCnorKey" id="wtfCnorKey" >
<option value="" selected="selected">===全部===</option>
<c:forEach var="item" items="${fq}" varStatus="s">
<option value="${item.normKey}"
<c:if test="${item.normKey==vo.wtfCnorKey}">selected="selected"</c:if>>
${item.normName}</option>
</c:forEach>
</select><font color="red" id="bailNormlimit_Type"> *</font>
</p>
<p>
<label>Participant Package:</label>
<select class="required combox" name="stdCnorKey" id="stdCnorKey">
<option value="" selected="selected">===全部===</option>
<c:forEach var="item" items="${fq}" varStatus="s">
<option value="${item.normKey}"
<c:if test="${item.normKey==vo.stdCnorKey}">selected="selected"</c:if>>
${item.normName}</option>
</c:forEach>
</select><font color="red" id="bailNormlimit_Type"> *</font>
</p>