从后台获取二维码base64码

success: res => {

// console.log(res.data.data)

var imgSrc = res.data.data;//base64编码

var save = wx.getFileSystemManager();

var number = Math.random();

//保存本地图片文件路径，也是绘图路径

let filePath = wx.env.USER_DATA_PATH + '/pic' + number + '.png'

save.writeFile({

filePath: filePath,

data: imgSrc,

encoding: 'base64'

success: res2 => {

wx.saveImageToPhotosAlbum({

filePath: filePath,

success: function (res2) {

console.log(res2)

// wx.showToast({

// title: '保存成功',

// })

if (res.data.data) {

//这是封装的模板，赋值

that.setData({

shareThree: {

avatar: userInfo.avatarUrl,

nickname: userInfo.nickName,

awardMoney: that.data.positionArr.jobName,

showShareModel: true

ErWeiMa: filePath,

awardContent: that.data.positionArr.nature + ' | ' + that.data.positionArr.city

}

})

}

}

})

}

})

}

另外，如果是从后台返回直接的图片路径，就需要先下载，用下载后返回的路径绘图

//下载二维码

//console.log(that.data.ErWeiMa)

// wx.downloadFile({

// url: that.data.ErWeiMa,

// success: function (res) {

// //console.log(res)

// if (res.statusCode == 200) {

// that.setData({

//设置ctx.drawImage(that.data.ErWeiMa, *，*，*)地址

// QRPath: res.tempFilePath

// })

// that.drawImage();

// }

// },

// fail: function () {

// that.showErrorModel('网络错误');

// }

// })