Azure Blob Storage With ASP.NET Core

-
Azure Blob Storage With ASP.NET Core

This blog will show you how to create a container and files in Azure Blob Storage.

You must first install the Azure.Storage.Blobs package.

Install-Package Azure.Storage.Blobs

Create a container in Azure Blob Storage

Let's start by learning how to create a container in Azure Blob Storage. A connection string is required for this. Go to Azure Blob Storage -> Access keys for that. There are two key values there. Choose the first option. The connection string will be concealed. When you click the show button on the right side, the connection string will be revealed. You can now copy the connection string.

Azure Blob Storage With ASP.NET Core

A code snippet for creating a container in Azure Storage is provided below. The connection string has been set up here. The instance of BlobContainerClient has been created. Using the BlobContainerClient instance, determine whether the container name exists or not, and if not, create a new container with the given name.

The container name must adhere to the following guidelines.

  1. The container name must have between 3 and 63 characters.
  2. It should begin with a letter or a number, and it should only contain letters, numbers, and the hyphen.
  3. Lowercase letters must be used in blob container names.
HomeController.cs
using Azure.Storage.Blobs;

public IActionResult CreateConatiner(string conatinerNameText)
{
    string connectionString = "DefaultEndpointsProtocol=https;AccountName=customerstorage;AccountKey=RgQcRTzDCaseT3DBa71JhpCZqbNLlsfbkK+9DnOq85++wlWxuhK1g;EndpointSuffix=core.windows.net";

    BlobContainerClient container = new(connectionString, conatinerNameText);

    if (!container.Exists())
    {
        container.Create();

        ViewBag.CreateMsg = "Container Successfully Created";
    }
    else
    {
        ViewBag.CreateMsg = "Container Already Exist";
    }

    return View("Index");
}

The view code is as follows. It receives container names and sends them to the controller.

Index.cshtml
<form method="post" asp-controller="Home" asp-action="CreateConatiner">

  Enter container name: <input id="conatinerNameText" name="conatinerNameText" type="text" />
  <br />
  <input type="submit" value="Create Container" />
  <div style="color:green">@ViewBag.CreateMsg</div>
</form>

The above code produced the following result. In this case, the sample container was created in Azure storage.

Azure Blob Storage With ASP.NET Core

Upload File/Object to Azure Blob Storage Container

The code below assists in uploading the file to the Azure Blob Storage Container. The GetBlobClient() method appends blob names to the end of Uri to create a new BlobClient object. The code then determines whether or not the files already exist in the container. If the file already exists, the message "File Already Exist" is displayed; otherwise, the file is uploaded to an Azure storage container.

public IActionResult Upload(IFormFile uploadFile)
{
    string connectionString = "DefaultEndpointsProtocol=https;AccountName=customerstorage;AccountKey=RgQcRTzDCaseT3DBa71JhpCZqbNLlsfbkK+9DnOq85++wlWxuhK1g;EndpointSuffix=core.windows.net";

    BlobContainerClient container = new(connectionString, "sample");

    BlobClient blob = container.GetBlobClient(uploadFile.FileName);

    if (!blob.Exists())
    {
        using (var memoryStream = new MemoryStream())
        {
            uploadFile.CopyTo(memoryStream);
            memoryStream.Position = 0;
            var result = blob.Upload(memoryStream);
        }

        ViewBag.CreateMsg = "File Uploaded Successfully";
    }
    else
    {
        ViewBag.CreateMsg = "File Already Exist";
    }

    return View("Index");
}

The code for a razor page is as follows. To upload the file, it has a file upload and submit button element.

<form method="post" enctype="multipart/form-data" asp-controller="Home" asp-action="Upload">
  <div class="form-group">
      <div class="col-md-10">
          <p>Upload File:</p>
          <input type="file" name="uploadFile" />
      </div>
  </div>
  <div class="form-group">
      <div class="col-md-10">
          <input type="submit" value="Upload" />
      </div>
  </div>
      <div style="color:green">@ViewBag.CreateMsg</div>
</form>

The image below is the result of the above code. It demonstrates how the file was uploaded to the Azure storage container.

Azure Blob Storage With ASP.NET Core

List Azure Blob Container Files

The following code shows how to get a list of file names from an Azure blob container. Using the GetBlobs() method, the following code retrieves all of the files from the sample container. It collects the names of the blob files using a foreach loop and sends them to the view to display.

public IActionResult Index()
{
    string connectionString = "DefaultEndpointsProtocol=https;AccountName=customerstorage;AccountKey=RgQcRTzDCaseT3DBa71JhpCZqbNLlsfbkK+9DnOq85++wlWxuhK1g;EndpointSuffix=core.windows.net";

    BlobContainerClient container = new(connectionString, "sample");
    List<string> blobList = new List<string>();
    var blobs = container.GetBlobs();

    foreach (BlobItem blob in blobs)
    {
       blobList.Add(blob.Name);
    }

    return View(blobList);
}

The following is a razor page code that displays the name of the blob files using a table.

@model List<string>

<table class="table">
    <thead>
        <tr>
            <th scope="col">File Name</th>
        </tr>
    </thead>
    <tbody>
        @foreach (var item in Model)
        {
            <tr>
            <td>@item</td>
            </tr>
        }
    </tbody>
</table>

The above code produced the following result. It displays a list of blob files found in the 'sample' Azure container.

Azure Blob Storage With ASP.NET Core

Download Azure Blob Container File

The code below shows how to download an Azure blob container file. The code below downloads the file that was downloaded via MemoryStream. The file type was then determined using the file extension method, and the file was downloaded.

public IActionResult Download(string fileName)
{
    string connectionString = "DefaultEndpointsProtocol=https;AccountName=customerstorage;AccountKey=RgQcRTzDCaseT3DBa71JhpCZqbNLlsfbkK+9DnOq85++wlWxuhK1g;EndpointSuffix=core.windows.net";

    // sample is a name of the container
    BlobClient blob = new (connectionString, "sample", fileName);
    MemoryStream ms = new ();
    blob.DownloadTo(ms);

    var ext = Path.GetExtension(fileName);
    string contentType = "";
    if (ext == ".pdf")
    {
        contentType = "application/pdf";
    }

    return File(ms.ToArray(), contentType, fileName);
}

The code for a razor page is as follows. The download link for the files has been added here.

@model List<string>

<table class="table">
    <thead>
        <tr>
            <th scope="col">File Name</th>
            <th scope="col">Download</th>
        </tr>
    </thead>
    <tbody>
        @foreach (var item in Model)
        {
            <tr>
            <td>@item</td>
            <td><a href='Home/download?fileName=@item'>Download</a></td>
            </tr>
        }
    </tbody>
</table>

The following is a output of the above code

Download Azure Blob Storage file With ASP.NET Core

Delete Azure Blob Container File

The code examples below show how to delete a file from the Azure Blob Storage Container. The code checks whether or not the 'sample' container and the given file name exist. The file is then deleted if it exists.

public IActionResult Delete(string fileName)
{
    string connectionString = "DefaultEndpointsProtocol=https;AccountName=customerstorage;AccountKey=RgQcRTzDCaseT3DBa71JhpCZqbNLlsfbkK+9DnOq85++wlWxuhK1g;EndpointSuffix=core.windows.net";

    BlobContainerClient container = new BlobContainerClient(connectionString, "sample");

    if (container.Exists())
    {
        BlobClient blob = container.GetBlobClient(fileName);

        if (blob.Exists())
        {
            blob.DeleteIfExists();
            ViewBag.CreateMsg = "File Deleted Successfully";
        }
        else
        {
            ViewBag.CreateMsg = "File Not Available";
        }
    }

    // Code to get a list of files
    …
    …
    …
    return View("Index", blobList);
}

The code for a razor page is as follows. To delete the files, a delete link has been added here.

@model List<string>
  <div style="color:green">@ViewBag.CreateMsg</div>
  <table class="table">
      <thead>
          <tr>
              <th scope="col">File Name</th>
              <th scope="col">Download</th>
              <th scope="col">Delete</th>
          </tr>
      </thead>
      <tbody>
          @foreach (var item in Model)
          {
              <tr>
                  <td>@item</td>
                  <td><a href='Home/download?fileName=@item'>Download</a></td>
                  <td><a href='Home/delete?fileName=@item'>Delete</a></td>
              </tr>
          }
      </tbody>
  </table>

The image below is the result of the above code. When the user clicked the delete link, the file was deleted from the Azure storage container.

Delete Azure Blob Storage files With ASP.NET Core

I hope this helps you. Keep coding.

Comments

Post a Comment

Popular posts from this blog

Entity Framework Core (EF) with SQL Server LocalDB

-
Image
This blog is going to illustrate how to implement Entity Framework (EF) Core with SQL Server LocalDB. The Entity Framework Core enables access to data from the database. This allows developers to avoid having to write most of the data access code. And the SQL Server LocalDB works similarly to the SQL SERVER with few features. You can get the LocalDB when you install visual studio or visual studio express. You can find the .mdf and _log.ldf files in the C:/Users/{user} directory. Let see how to create a SQL Server LocalDB and implement Entity Framework Core Step 1: The first step is to add a connection. In the menu -> click Tools and select Connect to Database It will display the Add Connection window. Enter (localdb)\mssqllocaldb in the server name textbox. Then in the Select or enter a database, select master and click ok Now in the server explorer, you can find the master DB containing Tables, Views, Stored
Read more

SignalR with JavaScript in ASP.NET Core MVC

-
Image
This blog is going to explain what is SignalR and how to implement it in ASP.NET Core. SignalR is a real time application framework for ASP.NET Core. Using SignalR you can provide updated information without refreshing the page, for example poll results, game score, chat etc. Let's see how to achieve it in ASP.NET Core MVC. Step 1: First step I added the SignalR client library. To add a SignalR client library, Right click on the project in Solution Explorer and Add -> Client-Side Library. Select the provider as unpkg as shown in the image below. Enter the latest version of SignalR into the library. And selected signalr.js and signalr.min.js files. Finally clicked the install button to install the client library. Step 2: At this step I have created a VoteHub.cs class inside the Hubs folder(create a new folder called Hubs). This class inherits from the Hub class which is a base class of SignalR hub. The SendMessage method will be called by the connected client.
Read more

Localization in ASP.NET Core MVC with Example

-
Image
Using Query Strings for Request Culture and Simplifying Localization with IStringLocalizer Interface Let’s see how to implement Localization in ASP.NET Core MVC. In the first example, I am going to use the IStringLocalizer Interface in the controller to implement Localization. Additionally, when the user passes the desired language through the query string, it will display content in that language. First, let’s configure the settings in the program.cs file. builder.Services.AddLocalization(options => options.ResourcesPath = "Resources");  The AddLocalization method adds the localization service to the service container. I have added the supported cultures here. I have added two cultures: en for English and nl for Dutch. In the RequestCultureProviders , I have included QueryStringRequestCultureProvider() . This allows the system to determine the culture information from the query string. UseRequestLocalization initializes a RequestLocalizationOptions objec
Read more