Media examples

3 min

Media (such as files) are treated as any other content type but have associated binary data stored using BLOB providers, which are optimized for storing data streams.

The following example defines a simple content type that is used in the examples that follow it:

[ContentType]
public class GenericFile : MediaData {
  public string Description { 
    get; 
    set; 
  }
}

The following example creates a file and defines a simple text file with the message Hello world:

public void Uploading_a_file() {
  var contentRepository = ServiceLocator.Current.GetInstance<IContentRepository>();
  var blobFactory = ServiceLocator.Current.GetInstance<IBlobFactory>();

  //Get a new empty file data
  var file1 = contentRepository.GetDefault<GenericFile>(SiteDefinition.Current.GlobalAssetsRoot);
  file1.Name = "Readme.txt";

  //Create a blob in the binary container
  var blob = blobFactory.CreateBlob(file1.BinaryDataContainer, ".txt");
  using(var s = blob.OpenWrite()) {
    StreamWriter w = new StreamWriter(s);
    w.WriteLine("Hello world");
    w.Flush();
  }

  //Assign to file and publish changes
  file1.BinaryData = blob;
  var file1ID = contentRepository.Save(file1, SaveAction.Publish);
}

The following example creates a location where the actual file type is resolved during runtime from the extension:

public void Uploading_a_media_from_extension() {
  var contentRepository = ServiceLocator.Current.GetInstance<IContentRepository>();
  var contentTypeRepository = ServiceLocator.Current.GetInstance<IContentTypeRepository>();
  var mediaDataResolver = ServiceLocator.Current.GetInstance<ContentMediaResolver>();
  var blobFactory = ServiceLocator.Current.GetInstance<IBlobFactory>();

  //Get a suitable MediaData type from extension
  var mediaType = mediaDataResolver.GetFirstMatching(".txt");
  var contentType = contentTypeRepository.Load(mediaType);

  //Get a new empty file data
  var media = contentRepository.GetDefault<MediaData>(SiteDefinition.Current.GlobalAssetsRoot, contentType.ID);
  media.Name = "Readme.txt";

  //Create a blob in the binary container
  var blob = blobFactory.CreateBlob(media.BinaryDataContainer, ".txt");
  using(var s = blob.OpenWrite()) {
    StreamWriter w = new StreamWriter(s);
    w.WriteLine("Hello world");
    w.Flush();
  }

  //Assign to file and publish changes
  media.BinaryData = blob;
  var file1ID = contentRepository.Save(media, SaveAction.Publish);
}

The following example updates an existing file with metadata:

public void UpdatingMetaData_of_a_file() {
  var contentRepository = ServiceLocator.Current.GetInstance<IContentRepository>();
  var blobFactory = ServiceLocator.Current.GetInstance<IBlobFactory>();

  //the file to update, not hardcoded of course
  var fileID = new ContentReference(444);

  //Get the file
  var file1 = contentRepository.Get<GenericFile>(fileID).CreateWritableClone() as GenericFile;

  //Update description
  file1.Description = "My description";

  //Publish
  var file1ID = contentRepository.Save(file1, SaveAction.Publish);

}

The following example updates an existing file with binary data:

public void UpdatingBinary_of_a_file() {
  var contentRepository = ServiceLocator.Current.GetInstance<IContentRepository>();
  var blobFactory = ServiceLocator.Current.GetInstance<IBlobFactory>();

  //the file to update, not hardcoded of course
  var fileID = new ContentReference(444);

  //Get the file
  var file1 = contentRepository.Get<GenericFile>(fileID).CreateWritableClone() as GenericFile;

  //Upload new blob
  var blob = blobFactory.CreateBlob(file1.BinaryDataContainer, ".txt");
  using(var s = blob.OpenWrite()) {
    StreamWriter w = new StreamWriter(s);
    w.WriteLine("Hello world");
    w.Flush();
  }

  //Assign to file and publish changes
  file1.BinaryData = blob;
  var file1ID = contentRepository.Save(file1, SaveAction.Publish);
}

See BLOB storage and providers to change the storage model for media.