So verwenden Sie die dreistufige Verknüpfungsauswahl des WeChat-Applets

<view class="tui-picker-content">
 <view class="tui-picker-name">一级选择实例</view>
 <picker bindchange="changeCountry" value="{{countryIndex}}" range="{{countryList}}">
 <view class="tui-picker-detail">{{countryList[countryIndex]}}</view>
 </picker>
</view>

<view class="tui-picker-content">
 <view class="tui-picker-name">省市区三级联动选择</view>
 <picker bindchange="changeRegin" mode = "region" value="{{region}}">
 <view class="tui-picker-detail">{{region[0]}} - {{region[1]}} - {{region[2]}}</view>
 </picker>
</view>

<view class="tui-picker-content">
 <view class="tui-picker-name">自定义二级联动选择</view>
 <picker bindchange="changeMultiPicker" mode = "multiSelector" value="{{multiIndex}}" range="{{multiArray}}">
 <view class="tui-picker-detail">
 {{multiArray[0][multiIndex[0]]}} * {{multiArray[1][multiIndex[1]]}} = {{multiArray[0][multiIndex[0]] * multiArray[1][multiIndex[1]]}}
 </view>
 </picker>
</view>

<view class="tui-picker-content">
 <view class="tui-picker-name">自定义三级联动选择</view>
 <picker bindchange="changeMultiPicker3" mode = "multiSelector" value="{{multiIndex3}}" range="{{multiArray3}}">
 <view class="tui-picker-detail">
 {{multiArray3[0][multiIndex3[0]]}} * {{multiArray3[1][multiIndex3[1]]}} * {{multiArray3[2][multiIndex3[2]]}} = {{multiArray3[0][multiIndex3[0]] * multiArray3[1][multiIndex3[1]] * multiArray3[2][multiIndex3[2]]}}
 </view>
 </picker>
</view>

page{background-color: #efeff4;}
.tui-picker-content{
 padding: 30rpx;
 text-align: center;
}
.tui-picker-name{
 height: 80rpx;
 line-height: 80rpx;
}
.tui-picker-detail{
 height: 80rpx;
 line-height: 80rpx;
 background-color: #fff;
 font-size: 35rpx;
 padding: 0 10px;
 overflow: hidden;
}

Page({
 data: {
 // 普通选择器列表设置,及初始化
 countryList: ['中国','美国','英国','日本','韩国','巴西','德国'],
 countryIndex: 6,
 // 省市区三级联动初始化
 region: ["四川省", "广元市", "苍溪县"],
 // 多列选择器(二级联动)列表设置,及初始化
 multiArray: [[1, 2, 3, 4, 5, 6, 7, 8, 9], [1, 2, 3, 4, 5, 6, 7, 8, 9]],
 multiIndex: [3,5],
 // 多列选择器(三级联动)列表设置,及初始化
 multiArray3: [[1, 2, 3, 4, 5, 6, 7, 8, 9], [1, 2, 3, 4, 5, 6, 7, 8, 9], [1, 2, 3, 4, 5, 6, 7, 8, 9]],
 multiIndex3: [3, 5, 4]
 },
 // 选择国家函数
 changeCountry(e){
 this.setData({ countryIndex: e.detail.value});
 },
 // 选择省市区函数
 changeRegin(e){
 this.setData({ region: e.detail.value });
 },
 // 选择二级联动
 changeMultiPicker(e) {
 this.setData({multiIndex: e.detail.value})
 },
 // 选择三级联动
 changeMultiPicker3(e) {
 this.setData({ multiIndex3: e.detail.value })
 }
})