/// <summary> /// 从网络上面下载图片,转换成 BitMapImage /// </summary> /// <param name="url">图片的 url 地址</param> /// <param name="bufferSize">读取图片开辟的缓存大小,默认 512K</param> /// <returns></returns> public static async Task <ImageSource> FetchImage(string url) { if (CloudStorageHelper.IsCloudImage(url) && !FileCacheHelper.IsCached(url)) { var storage = CloudStorageHelper.GetCloudStorage(); await storage.GetImage(url, FileCacheHelper.AppCacheDirectory, FileCacheHelper.BuildFileName(url)); } var stream = FileCacheHelper.Hit(url); return(LoadImageStream(stream)); }