在下面的代码中后台js想用不同的选择器对应的data-id, 但是后台打印出来永远是lists的最后index的值：在这里想要每一个index下的data-id值。

<block wx:for="{{lists}}" wx:key="{{index}}">

<van-field required class="shangpin_div"  value="" name="commodity" label="商品名称{{index+1}}" placeholder="请输入商品名称" data-id='{{index}}' bindchange="bindCommodityDataChang" />

<van-field

value="{{unitOfMeasureShow[index]}}"

required

clearable

label="计量单位"

readonly="true"

icon="exchange"

placeholder="请选择计量单位"

bind:click-icon="onClickIcon"

/>

<van-popup

show="{{ show }}"

position="bottom"

overlay="{{ false }}"

bind:close="onClose"

>

<van-picker

show-toolbar

title="计量单位"

columns="{{ unitOfMeasurement }}"

bind:cancel="onCancel"

bind:confirm="onChangeUnitMeasure"

data-id='{{index}}'

/>

</van-popup>

<van-field class="shangpindanjia_div" type ="number" value="" name="commodityprice" label="商品单价" required placeholder="请输入商品单价" data-id='{{index}}' bindchange="addCommodityPrice" />

</block>