Question

我正在编写一个程序，可以从Azure存储容器中的指定文件路径下载图像。

我已将在线代码中的以下函数放在一起，然后删除错误。但是，我无法摆脱最后的错误。

以下完整代码：

using System;
using System.Windows.Forms;
using Microsoft.WindowsAzure.Storage;

using Microsoft.WindowsAzure.Storage.Blob;
using System.IO;
namespace WarehousePhotoProgram
{
    public partial class Form1 : Form
    {
        string storageConnectionString = Environment.GetEnvironmentVariable("storageconnectionstring");

    public Form1()


       {
            InitializeComponent();
        }

        private void DownloadFileFromBlob(string fileName, string containerName)
        {
            CloudStorageAccount account = CloudStorageAccount.Parse(RoleEnvironment.GetConfigurationSettingValue(storageConnectionString));
            CloudBlobClient blobClient = account.CreateCloudBlobClient();
            CloudBlobContainer container = blobClient.GetContainerReference(containerName);
            CloudBlob blob = container.GetBlobReference(fileName);
            MemoryStream memStream = new MemoryStream();
            blob.DownloadToStream(memStream);
            Response.ContentType = blob.Properties.ContentType;
            Response.AddHeader("Content-Disposition", "Attachment; filename=" + fileName.ToString());
            Response.AddHeader("Content-Length", blob.Properties.Length.ToString());
            Response.BinaryWrite(memStream.ToArray());

        }
    }
   }

RoleEnvironment上的代码当前错误，说明命名空间不存在，我是否缺少程序集引用？或者我是否需要导入另一个using。第二个错误出现在Result.的所有Response上，表明RoleEnvironment不存在。

这也是从BlobStorage下载图像的最佳方法，还是应该采用其他方法？

编辑：我在给定答案的帮助下解决了public Form1() { InitializeComponent(); //_storageAccount = CloudStorageAccount.Parse(storageConnectionString); DownloadFileFromBlob("029000/1.png", "warehouseimages", "Desktop"); } private void DownloadFileFromBlob(string fileName, string containerName, string localFilePath) { CloudStorageAccount account = CloudStorageAccount.Parse(storageConnectionString); CloudBlobClient blobClient = account.CreateCloudBlobClient(); CloudBlobContainer container = blobClient.GetContainerReference(containerName); CloudBlob blob = container.GetBlobReference(fileName); using (var fileStream = System.IO.File.OpenWrite(localFilePath)) { blob.DownloadToStream(fileStream); MessageBox.Show("SUCCESS"); } }错误。现在尝试确定代码的Response部分也需要改变。

SurfaceView

Answer 1

RoleEnvironment类是Microsoft.WindowsAzure.ServiceRuntime命名空间的一部分，我从旧的经典云服务中知道。

您应该使用 ConfigurationManager 来检索您的设置。

请参阅Configuration in ASP.NET Core或者如果您使用.NET完整框架，请阅读更多相关信息here。

Answer 2

如果要将图像下载到本地磁盘，可以按如下方式修改代码：

    /// <summary>
    /// Download File From Blob
    /// </summary>
    /// <param name="fileName">For example: image.PNG</param>
    /// <param name="containerName">container name of blob</param>
    /// <param name="localFilePath">For example: @"C:\Test\BlobTest.PNG"</param>
    private void DownloadFileFromBlob(string fileName, string containerName, string localFilePath)
    {
        CloudStorageAccount account = CloudStorageAccount.Parse("Your connection string");
        CloudBlobClient blobClient = account.CreateCloudBlobClient();
        CloudBlobContainer container = blobClient.GetContainerReference(containerName);
        CloudBlob blob = container.GetBlobReference(fileName);
        using (var fileStream = System.IO.File.OpenWrite(localFilePath))
        {
            blob.DownloadToStream(fileStream);
        }
    }

从Azure Blob Storage下载图像

2 个答案: