将位图流上传到 Azure 存储时，它存储零/空图像答案

【问题标题】：When upload Bitmap stream to Azure storage, it store zero/empty image将位图流上传到 Azure 存储时，它存储零/空图像
【发布时间】：2015-08-27 08:11:44
【问题描述】：

我正在使用以下代码将 MemoryStream 从位图图像上传到我的 Microsoft azure 存储帐户：

                         MemoryStream memoryStream = new MemoryStream();

                       img.Save(memoryStream, System.Drawing.Imaging.ImageFormat.Png);

                       blob.Properties.ContentType = model.File.ContentType;
                       blob.UploadFromStream(memoryStream);

使用上面的代码会发生什么，它将一个空图像上传到 Azure 存储:(！（我找到了名称，但文件大小为零！）！

       if (model.File != null && model.File.ContentLength > 0)
                {
                    Bitmap original = null;
                    var name = "newimagefile";
                    var errorField = string.Empty;

                    errorField = "File";
                    name = Path.GetFileNameWithoutExtension(model.File.FileName);
                    original = Bitmap.FromStream(model.File.InputStream) as Bitmap;
                   if (original != null)
                     {
                       var img = CreateImage(original, model.X, model.Y, model.Width, model.Height);



                       CloudStorageAccount storageAccount = CloudStorageAccount.Parse(
                                   CloudConfigurationManager.GetSetting("StorageConnectionString"));

                       CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();

                       CloudBlobContainer container = blobClient.GetContainerReference("company"); // must always be lowercase
                                                 container.CreateIfNotExists();

                       container.SetPermissions(
       new BlobContainerPermissions
       {
           PublicAccess =
               BlobContainerPublicAccessType.Blob
       });


                       CloudBlockBlob blob = container.GetBlockBlobReference(imgName + ".png");

                       MemoryStream memoryStream = new MemoryStream();

                       img.Save(memoryStream, System.Drawing.Imaging.ImageFormat.Png);

                       blob.Properties.ContentType = model.File.ContentType;
                       blob.UploadFromStream(memoryStream);

}

请帮忙！

【问题讨论】：

标签： asp.net-mvc azure cloud

【解决方案1】：

我认为您需要在上传之前将位置设置回流的开头

img.Save(memoryStream, System.Drawing.Imaging.ImageFormat.Png);
blob.Properties.ContentType = model.File.ContentType;
memoryStream.Position = 0;
blob.UploadFromStream(memoryStream);

【讨论】：