微信小游戏使用云开发,下载prefab预制资源,下载后文件类型为.bin,无法加载为.prefab

微信小游戏使用云开发,下载prefab预制资源,下载后文件类型为.bin,无法加载为.prefab。

请问各位大神,如何处理?

下载:
wx.cloud.downloadFile({

                    fileID: xiazaiid, // 文件 ID

                    success: res => {

                        Global.yixiazaidizhi_prefab[xzprefab]=res.tempFilePath;

                        var zhongzhuanshuzi=Global.xiazaichenggonggeshu;

                        Global.xiazaichenggonggeshu=zhongzhuanshuzi+1;

                        console.log('prefab...res.tempFilePath='+Global.yixiazaidizhi_prefab[xzprefab]);

                        console.log('Global.xiazaichenggonggeshu...success...'+Global.xiazaichenggonggeshu);

                    },

                    fail: res => {

                        console.log(res+'...1');

                    },

                })

加载:
for(var jzprefab in Global.yixiazaidizhi_prefab){

        cc.resources.load(Global.yixiazaidizhi_prefab[jzprefab], cc.Prefab, null,function(err,prefab){

            Global.prefab[this]=prefab; 

            console.log('this...'+this);

            console.log('Global.prefab[this]...'+Global.prefab[this]);

        }.bind(jzprefab));

    };

临时地址:
http://tmp/TLt7DJvAVSwE650a227024fced75636ba2a68babf10d.bin

打印结果:
index.js:1 this…xueliangbianhua
Global.prefab[this]…undefined