Visual Basic 2005: A Developer's Notebook

Upload and Download Files with FTP

Earlier versions of .NET didn't include any tools for FTP (File Transfer Protocol), a common protocol used to transfer files to and from a web server. As a result, you either had to purchase a third-party component or write your own (which was easy in principle but difficult to get right in practice).

Note

Need to upload files to an FTP site or download existing content? New support is available in VB 2005.

In .NET 2.0, a new FtpWebRequest class neatly fills the gap. However, the FtpWebRequest class has its own complexities, so Microsoft programmers simplified life for VB developers even further by extending the My.Computer.Network object to provide two quick access methods for completing basic FTP operations. These are UploadFile(), which sends a file to a remote server, and DownloadFile( ), which retrieves a file and stores it locally.

How do I do that?

Whether you use the FtpWebRequest class or the My.Computer.Network object, all FTP interaction in .NET is stateless. That means that you connect to the FTP site, perform a single operation (like transferring a file or retrieving a directory listing), and then disconnect. If you need to perform another operation, you need to reconnect. Fortunately, this process of connecting and logging in is handled automatically by the .NET Framework.

The easiest way to use FTP in a VB application is to do so through the My.Computer.Network object. If you use its FTP methods, you never need to worry about the ...