CreateBlob Method

Creates a new blob or updates the content of an existing blob within a container.

Syntax

[VB.NET]
Public Sub CreateBlob(ByVal blobName As String)

[C#]
public void CreateBlob(string blobName);

Remarks

This method is used to create a new blob with the name blobName and stored within the container specified in ContainerName. If blobName already exists within the container, the entire existing content of the blob will be overwritten with the new content (this includes existing metadata).

The content of the blob is specified by LocalFile or BlobData. BlobData will only be used when LocalFile is an empty string, otherwise the file specified within LocalFile will be used to create the blob content.

Any metadata specified in Metadata will be set for the created blob.

The Blob Azure service requires that all block blobs created in one request be less than 64 MB. If your blob content, specified by LocalFile or BlobData, is larger than 64 MB, CreateBlob will split the data into a set of blocks (each being less than or equal to 4 MB in size). Once split, each block will be uploaded one by one to the server (internally calling CreateBlock). During the uploading process, for each block that has been uploaded successfully, BlockList will be fired and all uploaded blocks are stored in Blocks. After all the blocks are uploaded, CreateBlob will use the blocks stored in Blocks to commit the blob content (internally calling PutBlockList).

During the upload process, StartByte records the current progress. If one block fails to upload, calling CreateBlob again will start from the position recored by StartByte. Setting StartByte to 0 forces a completely new upload, in which case Blocks will be cleared and any existing blocks that have been successfully uploaded will not be used to commit the blob content. After a successful upload StartByte is automatically reset to 0.

If the blob has an active lease, LeaseId must be specified prior to calling CreateBlob.

To encrypt blob content, EncryptionPassword can be set.