JS

var pageData = {
  data: {
    switch1Checked: true,
    switch2Checked: false,
    switch1Style: '',
    switch2Style: 'text-decoration: line-through'
  }
}
for (var i = 1; i <= 2; ++i) {
  (function (index) {
    pageData[`switch${index}Change`] = function (e) {
      console.log(`switch${index}发生change事件，携带值为`, e.detail.value)
      var obj = {}
      obj[`switch${index}Checked`] = e.detail.value
      this.setData(obj)
      obj = {}
      obj[`switch${index}Style`] = e.detail.value ? '' : 'text-decoration: line-through'
      this.setData(obj)
    }
  })(i)
}
Page(pageData)

XML

<view class="page">
    <view class="page__hd">
        <text class="page__title">switch</text>
        <text class="page__desc">开关</text>
    </view>
    <view class="page__bd">
        <view class="section section_gap">
            <view class="section__title">type="switch"</view>
            <view class="body-view">
                <switch checked="{{switch1Checked}}" bindchange="switch1Change"/>
            </view>
        </view>
        <view class="section section_gap">
            <view class="section__title">type="checkbox"</view>
            <view class="body-view">
                <switch type="checkbox" checked="{{switch2Checked}}" bindchange="switch2Change"/>
            </view>
        </view>
    </view>
</view>