Taro 保存base64 图片到相册

async saveThePhoto() {

let that=this;

wx.getSetting({//获取权限

    success(res) {

if (res.authSetting["scope.writePhotosAlbum"]) {//已经授权过

        that.saveImageToAlbumFn();

}else {

wx.authorize({

scope:"scope.writePhotosAlbum",

success(result) {//用户手动点击了同意

            that.saveImageToAlbumFn();

},

fail(result_err) {//用户点击了拒绝，再次弹窗一个授权的提示框，否则用户拒绝后，无法再次授权【同意】

            that.setState({

openSetting:true,

})

}

});

}

},

fail(err) {

console.log(err);

}

});

}

//保存至相册

saveImageToAlbumFn =()=>{

let {codeImg}=this.state;

const fileManager = wx.getFileSystemManager();

let timestamp =new Date().getTime();

let that=this;

fileManager.writeFile({//下载文件资源到本地，客户端直接发起一个HTTP GET 请求，返回文件的本地临时路径

    filePath:`${wx.env.USER_DATA_PATH}/qrcode_${timestamp}.png`,

data:codeImg.slice(22),

encoding:"base64",

success(result) {

that.closeOpenSet();//关闭相册授权框

      Taro.saveImageToPhotosAlbum({

filePath:`${wx.env.USER_DATA_PATH}/qrcode_${timestamp}.png`,

}).then(getImageInfoResult => {

if (getImageInfoResult.errMsg ==='saveImageToPhotosAlbum:ok') {

Taro.showToast({

title:'图片已保存到相册',

icon:'none',

duration:1000

          })

}else {

Taro.showToast({

title:'图片保存失败',

icon:'none',

duration:1000

          })

}

});

},

fail(result_res){

console.log(result_res)

}

});

}

//关闭 相册授权框

closeOpenSet = () => {

this.setState({

openSetting:false

  })

}

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保存二维码需要授权'保存图片到相册'

取消

this.saveThePhoto()}>确定