1. chooseImage 选择图片

eg:

chooseImage(e) {
    const _index = app.getDataset(e, 'index')
    app.chooseImage().then((tempFilePaths) => {
      const path = tempFilePaths[0]
      if (_index == 0) {
        this.idCardPre = true
        // this.idCardPreUrl = path
        this.setData({ idCardPreUrl: path, formStatus: this.idCardPre && this.idcardBadge })
      } else {
        this.idcardBadge = true
        // this.idcardBadgeUrl = path
        this.setData({ idcardBadgeUrl: path, formStatus: this.idCardPre && this.idcardBadge })
      }
      return false
    }).catch(() => { })
  },

2. extendPage合并页面
   注：一般用于注册页面合并公共方法（例如使用分页）

4. getDataset获取当前元素上面的dataset里面的值

eg：

<image data-index = "0"  class="idcard-pos" bindtap = "chooseImage" src="{{idCardPreUrl}}" />
// js
chooseImage(e) {
    const _index = app.getDataset(e, 'index')
    

5. creatObj生成对象，只支持单个

eg:

const name = '0'
app.creatObj(`arr[${name}]`, 0) // {'arr[0]':0}
// 使用setData如下比较方便
this.setData({
'arr[0]':0,
'test.t': 9
})

6. readFile读取文件

eg:

 _getFile() {
    return Promise.all([app.readFile(this.data.idCardPreUrl), app.readFile(this.data.idcardBadgeUrl)])
      .then(flies => {
        const data = {}
        data.idFrontSide = flies[0]
        data.idBackSideQUERY = flies[1]
        data.idFrontSideName = 'webcat' + parseInt(Math.random() * 1000)
        data.idBackSideName = 'webcat' + parseInt(Math.random() * 1000)
        return data
      }).catch(() => { })
  },

7. request请求

eg:

app.request({
        url: this.data.apis.url,
        data: _data
      }).then(data => {
        ....
        return data
      }).catch((data, code) => {
        ....
      })

8. serialize序列化参数
   返回key1=1&key2=1字符串

9. toast提示信息