//select添加 field， option使用 selected
<div class="form-group">
    <label class="col-sm-3 control-label">新能源车购置</label>
        <div class="col-sm-8">
            <select placeholder="活动参与" th:field="*{ev}"     name="ev" class="form-control"  id="ev"  type="text" required>
                <option value="1"  th:selected="${ev == 1}" >参与   以旧换新</option>
                <option value="0"  th:selected="${ev == 0}">不参与 以旧换新</option>
            </select>
        </div>
</div>



//ruoyi项目中的 字符分割
<div class="form-group">
      <div th:each="image : ${#strings.listSplit(webProduct.pic,';')}">
          <label class="col-sm-3 control-label">产品图片：</label>
          <div class="col-sm-8">
              <img th:src="${image}"  id="imagepath1" name="imagepath" style="width: 210px;height: 210px">
          </div>
      </div>
</div>