angularjs实现下拉列表的选中事件示例

<select style="height:31px; width:100px" id="rewardMethod"name="rewardMethod" class="status_select" ng-model="state">
<option value="0" ng-selected='rewardMethod == "0"'>自动发放</option>
<option value="1" ng-selected='rewardMethod == "1"'>指定中奖人</option>
<option value="2" ng-selected='rewardMethod == "2"'>不发放奖品</option>
</select>

<div class="form-group" ng-if="state != 2">
            <label class="col-sm-3 control-label no-padding-right"
                for="form-field-1">优惠券</label>
            <div class="col-sm-9">
              <select style="height:31px; width:100px" id="reward"
                  name="reward" class="status_select">
                <option ng-repeat='item in couponList' ng-value="item.id"
                    ng-selected="couponInfoid == item.couponName">{{item.couponName}}
                  总数:{{item.countLimit}}
                </option>
              </select>
            </div>
          </div>
          <div class="form-group" ng-if="state == 0">
            <label class="col-sm-3 control-label no-padding-right"
                for="form-field-1"><span class="red">*</span>奖品发放数量</label>
            <div class="col-sm-9">
              <input type="text" name="rewardProvideCount" id="rewardProvideCount"
                  class="form-control"
                  check-type="required">
            </div>
          </div>
        </form>
      </div>