Io 在windows应用商店应用程序中显示下载的图像时出现异常

嗨，我正在从以下代码下载图像

            HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Get, imageUri);
            HttpResponseMessage response = await http.SendAsync(request, HttpCompletionOption.ResponseHeadersRead);
            var imageFile = await ApplicationData.Current.LocalFolder.CreateFileAsync(fileName, CreationCollisionOption.ReplaceExisting);
            var fs = await imageFile.OpenAsync(FileAccessMode.ReadWrite);
            DataWriter writer = new DataWriter(fs.GetOutputStreamAt(0));
            writer.WriteBytes(await response.Content.ReadAsByteArrayAsync());
            await writer.StoreAsync();
            writer.DetachStream();
            await fs.FlushAsync();
            fs.Dispose();

但当我尝试在运行下载代码后立即打开它时。。在以下代码的帮助下，尝试将其设置为图像控件的源代码

            var imageFile = await ApplicationData.Current.LocalFolder.GetFileAsync(imageName);
            IRandomAccessStream stream = await imageFile.OpenAsync(FileAccessMode.Read);
            imageControl.SetSource(stream);

它抛出以下异常

访问被拒绝。（HRESULT的例外：0x80070005（E_访问被拒绝））

内部例外是：

null

请让我知道在哪一点上我犯了错误

提前感谢

只需再添加一行。。现在下载的代码是

            HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Get, imageUri);
            HttpResponseMessage response = await http.SendAsync(request, HttpCompletionOption.ResponseHeadersRead);
            var imageFile = await ApplicationData.Current.LocalFolder.CreateFileAsync(fileName, CreationCollisionOption.ReplaceExisting);
            using (var fs = await imageFile.OpenAsync(FileAccessMode.ReadWrite))
            {
                var outStream = fs.GetOutputStreamAt(0);
                DataWriter writer = new DataWriter(outStream);
                writer.WriteBytes(await response.Content.ReadAsByteArrayAsync());
                await writer.StoreAsync();
                writer.DetachStream();
                await fs.FlushAsync();
                outStream.Dispose();
                fs.Dispose();
            }