回显带 forEach 循环的下拉框

<select class="combobox pull-left" id="updateProviderName"        style="margin-left: 10px;width: 185px">    <c:forEach items="${providerList}" var="prd">        <option value="${prd.providerId}"            <%-- 如果所选是之前的值 可以自动填写！ --%>            <c:if test="${prd.providerId==providerId}">selected = "selected"            </c:if> >            ${prd.providerName}        </option>    </c:forEach></select>