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Is there a way to add additional information for blob in Azure?

I want to store some relevant information, which connects the blob to other entity in in an a document database, for example a string which contains a JSON.

I know there is metadata for blob when I use Azure Storage explorer, but i want use it from code.

This a relevant question about this theme:
Adding Description/Metadata to Azure Blob

And how can retrieve the blobs based on this metadata?

Have you checked this link?

public static async Task AddContainerMetadataAsync(CloudBlobContainer container)

{

   // Add some metadata to the container.

   container.Metadata.Add("docType", "textDocuments");

   container.Metadata["category"] = "guidance";



   // Set the container's metadata.

   await container.SetMetadataAsync();

}

Keep in mind that

The name of your metadata must conform to the naming conventions for C# identifiers.

The first part of the question is answered by Mihail Stancescu, thank you!

The second part is not answered correctly yet. The Azure Search is a solution for it, but it is a totally other service. I want to solve this problem in my repository class. And i solved it.

Maybe it is interesting for someone else that is why I share my solution:

public IEnumerable<T> GetMany( Expression<Func<T, bool>> filter )

{

            return _AzureBlobCollection.BlobDirectory

                .ListBlobs( useFlatBlobListing: false, blobListingDetails: Microsoft.WindowsAzure.Storage.Blob.BlobListingDetails.Metadata )

                .OfType<Microsoft.WindowsAzure.Storage.Blob.CloudBlockBlob>()

                .Select<Microsoft.WindowsAzure.Storage.Blob.CloudBlockBlob, T>( blob => JsonConvert.DeserializeObject<T>( blob.Metadata[ "data" ] ) )

                .Where( filter.Compile() );

}

This function can call like this:
Repository repository = ..

IEnumerable files = repository.GetMany( f => f.Partner = "Microsoft" );

where file class is:

public class ContractFile : File

{

    public string Partner { get; set; }

    public Date CreationDate { get; set; }

    public string Remarks { get; set; }

    public string Filename { get; set; }

}

...

public class File

{

    public String File { get; set; }

    public Stream Data { get; set; }

}

And the insert is following:

    public void AddOne( T file )

    {

        file.id = Guid.NewGuid().ToString();

        Microsoft.WindowsAzure.Storage.Blob.CloudBlockBlob blob = _AzureBlobCollection.BlobDirectory.GetBlockBlobReference( file.id );



        blob.UploadFromStream( file.Data );

        blob.Metadata.Add( "data", JsonConvert.SerializeObject( file ) );

        blob.SetMetadata();

    }