VM40469:1 (in promise) MiniProgramError Cannot read property ‘setData‘ of undefined TypeError:

小程序this指向

wx.uploadFile({
          url: ‘’,
          filePath: ‘’,
          name: 'file',
          success: () => {
           this.setData({})
          }
        })
        ```
        success中无法拿到全局得this，this指向的是wx.uploadFile，把
        ```
        success () {
         this.setData({})
        }
        ```
        改成
        ```
        success: () => {
           this.setData({})
          }
        })
        ```
        就可以了