wx.cloud.downloadFile({ 
       fileID:fileID,
       success:res1=>{
        wx.getImageInfo({
          src:res1.tempFilePath,
          success (res) {
            console.log(res)
            that.setData({
              scalH:that.data.byclear/375*res.height*that.data.byclear/res.width
            })
            // console.log('this.data.scalH'+that.data.scalH)
            // console.log('this.data.scalH'+that.data.byclear)
            // console.log(res1.tempFilePath)
          console.log('检查下1')
          that.ctx.drawImage(res1.tempFilePath, 0, 0,  that.data.byclear, that.data.scalH);
          console.log('检查下2')
          that.ctx.fillText(that.data.userInfo.nickName, 20, 20)
          that.ctx.draw()
          }
        })
       } 
  })