<view class="savecode" bindtap=‘saveToPhone‘>
     保存二维码
  </view>

// 保存图片
saveToPhone(e){
  // let imgSrc =  e.currentTarget.dataset.url;  //要保存的图片url
  // console.log(imgSrc)
  wx.showLoading({
    title: ‘保存中...‘
  })
  wx.downloadFile({    //下载文件资源到本地
    url: this.data.imgUrl,
    success: function (res) {
      console.log(res);
      //图片保存到本地
      wx.saveImageToPhotosAlbum({
        filePath: res.tempFilePath,
        success: function (data) {
          wx.hideLoading()
          wx.showToast({
            title: ‘保存成功‘,
            icon: ‘success‘,
            duration: 2000
          })
        },
        fail: function (err) {
          if (err.errMsg === "saveImageToPhotosAlbum:fail auth deny" || err.errMsg === "saveImageToPhotosAlbum:fail:auth denied") {
            console.log("当初用户拒绝，再次发起授权")
            wx.showModal({
              title: ‘提示‘,
              content: ‘需要您授权保存相册‘,
              showCancel: false,
              success: modalSuccess => {
                wx.openSetting({
                  success(settingdata) {
                    console.log("settingdata", settingdata)
                    if (settingdata.authSetting[‘scope.writePhotosAlbum‘]) {
                      wx.showModal({
                        title: ‘提示‘,
                        content: ‘获取权限成功,再次点击图片即可保存‘,
                        showCancel: false,
                      })
                    } else {
                      wx.showModal({
                        title: ‘提示‘,
                        content: ‘获取权限失败，将无法保存到相册哦~‘,
                        showCancel: false,
                      })
                    }
                  },
                  fail(failData) {
                    console.log("failData", failData)
                  },
                  complete(finishData) {
                    console.log("finishData", finishData)
                  }
                })
              }
            })
          }
        },
        complete(res) {
          console.log(res);
          wx.hideLoading()
        }
      })
    }  
  })
},