Upload a Single File to Blob Storage Azure

using Microsoft.WindowsAzure.Storage;
using Microsoft.WindowsAzure.Storage.Auth;
using Microsoft.WindowsAzure.Storage.Blob;    

// Retrieve storage account from connection string.
    CloudStorageAccount storageAccount = CloudStorageAccount.Parse("StorageKey");

// Create the blob client.
CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();

// Retrieve reference to a previously created container.
CloudBlobContainer container = blobClient.GetContainerReference("mycontainer");

// Retrieve reference to a blob named "myblob".
CloudBlockBlob blockBlob = container.GetBlockBlobReference("myblob");

// Create or overwrite the "myblob" blob with contents from a local file.
using (var fileStream = System.IO.File.OpenRead(@"path\myfile"))
{
    blockBlob.UploadFromStream(fileStream);
}

see here about needed SDK and references

i think it's what you need

Since WindowsAzure.Storage is legacy. With Microsoft.Azure.Storage.* we can use the following code to upload

  static async Task CreateBlob()
    {
        
        BlobServiceClient blobServiceClient = new BlobServiceClient(storageconnstring);
        
        BlobContainerClient containerClient = blobServiceClient.GetBlobContainerClient(containerName);
        
        BlobClient blobClient = containerClient.GetBlobClient(filename);

        
        using FileStream uploadFileStream = File.OpenRead(filepath);
        
        await blobClient.UploadAsync(uploadFileStream, true);
        uploadFileStream.Close();
    }

The following code snippet is the simplest form of performing the file uploading. I have added a few more lines to this code, in order to detect the uploading file type and check the container exeistance.

Note:- you need to add the following NuGet packages first.

1. Microsoft.AspNetCore.StaticFiles

2. Microsoft.Azure.Storage.Blob

3. Microsoft.Extensions.Configuration

   static void Main(string[] args)
   {
       Console.WriteLine("Hello World!");
       string connstring = "DefaultEndpointsProtocol=https;AccountName=storageaccountnewne9d7b;AccountKey=3sUU8J5pQQ+6YYIi+b5jo+BiSb5XPt027Rve6N5QP9iPEhMXZAbzUfsuW7QDWi1gSPecsPFpC6AzmA9jwPYs6g==;EndpointSuffix=core.windows.net";
       string containername = "newturorial";
       string finlename = "TestUpload.docx";
       var fileBytes = System.IO.File.ReadAllBytes(@"C:\Users\Namal Wijekoon\Desktop\HardningSprint2LoadTest\" + finlename);
   
       var cloudstorageAccount = CloudStorageAccount.Parse(connstring);
       var cloudblobClient = cloudstorageAccount.CreateCloudBlobClient();
       var containerObject = cloudblobClient.GetContainerReference(containername);
   
       //check the container existance
       if (containerObject.CreateIfNotExistsAsync().Result)
       {
           containerObject.SetPermissionsAsync(new BlobContainerPermissions { PublicAccess = BlobContainerPublicAccessType.Blob });
       }
       var fileobject = containerObject.GetBlockBlobReference(finlename);
   
       //check the file type
       string file_type;
       var provider = new FileExtensionContentTypeProvider();
       if(!provider.TryGetContentType(finlename, out file_type))
       {
           file_type = "application/octet-stream";
       }
   
       fileobject.Properties.ContentType = file_type;
       fileobject.UploadFromByteArrayAsync(fileBytes, 0 , fileBytes.Length);
   
       string fileuploadURI = fileobject.Uri.AbsoluteUri;
       Console.WriteLine("File has be uploaded successfully.");
       Console.WriteLine("The URL of the Uploaded file is : - \n" + fileuploadURI);
   }
   

we can use BackgroundUploader class ,Then we need to provide StorageFile object and a Uri: Required Namespaces:

using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;
using Windows.Foundation;
using Windows.Foundation.Collections;
using Windows.Networking.BackgroundTransfer;
using Windows.Storage.Pickers;
using Windows.Storage;

The process is Like This : Uri is defined using a string value provided via a UI input field, and the desired file for upload, represented by a StorageFile object, is returned when the end-user has selected a file through the UI provided by the PickSingleFileAsync operation

Uri uri = new Uri(serverAddressField.Text.Trim());
FileOpenPicker picker = new FileOpenPicker();
picker.FileTypeFilter.Add("*");
StorageFile file = await picker.PickSingleFileAsync();

and Then:

BackgroundUploader uploader = new BackgroundUploader();
uploader.SetRequestHeader("Filename", file.Name);
UploadOperation upload = uploader.CreateUpload(uri, file);

// Attach progress and completion handlers.
await HandleUploadAsync(upload, true);

Thats All

Here is the complete method.

 [HttpPost]
        public ActionResult Index(Doctor doct, HttpPostedFileBase photo)
        {

            try
            {
                if (photo != null && photo.ContentLength > 0)
                {
                    // extract only the fielname
                    var fileName = Path.GetFileName(photo.FileName);
                    doct.Image = fileName.ToString();

                    CloudStorageAccount cloudStorageAccount = DoctorController.GetConnectionString();
                    CloudBlobClient cloudBlobClient = cloudStorageAccount.CreateCloudBlobClient();
                    CloudBlobContainer cloudBlobContainer = cloudBlobClient.GetContainerReference("images");


                    string imageName = Guid.NewGuid().ToString() + "-" +Path.GetExtension(photo.FileName); 

                    CloudBlockBlob BlockBlob = cloudBlobContainer.GetBlockBlobReference(imageName);

                    BlockBlob.Properties.ContentType = photo.ContentType;
                    BlockBlob.UploadFromStreamAsync(photo.InputStream);
                    string imageFullPath = BlockBlob.Uri.ToString();

                    var memoryStream = new MemoryStream();


                    photo.InputStream.CopyTo(memoryStream);
                    memoryStream.ToArray();



                    memoryStream.Seek(0, SeekOrigin.Begin);
                    using (var fs = photo.InputStream)
                    {
                        BlockBlob.UploadFromStreamAsync(memoryStream);
                    }

                }
            }
            catch (Exception ex)
            {

            }


            return View();
        }

where the getconnectionstring method is this.

 static string accountname = ConfigurationManager.AppSettings["accountName"];
      static  string key = ConfigurationManager.AppSettings["key"];


            public static CloudStorageAccount GetConnectionString()
            {

                string connectionString = string.Format("DefaultEndpointsProtocol=https;AccountName={0};AccountKey={1}", accountname, key);
                return CloudStorageAccount.Parse(connectionString);
            }

Complete Web API Controller to upload single or multiple files. .NET Framework 4.8

Install NuGet package, Azure.Storage.Blob

using Microsoft.WindowsAzure.Storage;
using Microsoft.WindowsAzure.Storage.Blob;
using System;
using System.Configuration;
using System.Web;
using System.Web.Http;

namespace api.azure.Controllers
{
    public class FileController : ApiController
    {
        [HttpPost]
        [Route("api/BlobStorage/UploadFiles")]
        public IHttpActionResult UploadFiles()
        {
            string result = "";
            try
            {
                result = UploadFilesToBlob();
            }
            catch (Exception ex)
            {
                return Ok(ex.Message);
            }

            return Ok(result);
        }

        public string UploadFilesToBlob()
        {
            try
            {
                string storageConnectionString = ConfigurationManager.AppSettings["BlobStorageConnectionString"];
                CloudStorageAccount blobStorage = CloudStorageAccount.Parse(storageConnectionString);
                CloudBlobClient blobClient = blobStorage.CreateCloudBlobClient();
                if (HttpContext.Current.Request.Form["BlobContainerName"] != null)
                {
                    string blobContainerName = HttpContext.Current.Request.Form["BlobContainerName"].ToString();
                    CloudBlobContainer container = blobClient.GetContainerReference(blobContainerName);
                    container.CreateIfNotExists();

                    // Set public access level to the container.
                    container.SetPermissions(new BlobContainerPermissions()
                    {
                        PublicAccess = BlobContainerPublicAccessType.Container
                    });

                    string folderName = "";
                    if (HttpContext.Current.Request.Form["FolderNameToUploadFiles"] != null)
                    folderName = HttpContext.Current.Request.Form["FolderNameToUploadFiles"].ToString() + "/";

                    for (int i = 0; i < HttpContext.Current.Request.Files.Count; i++)
                    {
                        var httpPostedFile = HttpContext.Current.Request.Files[i];
                        if (httpPostedFile != null)
                        {
                            string blobName = folderName + httpPostedFile.FileName;
                            CloudBlockBlob blob = container.GetBlockBlobReference(blobName);
                            blob.UploadFromStream(httpPostedFile.InputStream);
                        }
                    }
                }
            }
            catch (Exception ex)
            {
                throw ex;
            }

            return "# of file(s) sent to upload: " + HttpContext.Current.Request.Files.Count.ToString();

        }
    }
}