这样写 保存图品就没问题了

ondowntap(e) {

console.log("------", wx.env.USER_DATA_PATH + "/res");

var url = "https://mdapi.zjwist.com/mediainfo3/get/282264";

var that =this;

console.log("------", url);

wx.downloadFile({

url: url,

filePath: wx.env.USER_DATA_PATH + "/res"+"aa.png",

success: function (res) {

console.log("------", res);

var filePath =res.filePath;

wx.saveImageToPhotosAlbum({

filePath: filePath,

success(result) {

console.log("-----success-", result);

wx.showToast({

title: "下载完成",

icon: 'none',

duration: 1000,

});

}

})

},

fail: function (res) {

console.log("------fail", res);

wx.hideLoading()

}

})

}