wx.getSetting({

    success(res) {

        if (!res.authSetting[‘scope.writePhotosAlbum’]) {

            wx.authorize({

                scope: ‘scope.writePhotosAlbum’,

                success() {

                    // 申请授权成功

                },

                fail: err => {

                    // 授权失败，若是用户取消授权，短时间内不会再弹出授权窗口

                }

            })

        } else {

            // 已授权

        }

    },

    fail: err => {

    }

})