If you want to transfer an file or other object using the standard service as used by Windows' Wireless Link / Bluetooth File Transfer Wizard, Palm's Beam, Nokia's Send via Infrared, then use the OBEX protocol.

Only the PUT operation is supported, GET is not, nor is changing folders or getting a folder listing. There are some issue with handling file names that include non-English characters, and in the previous version connections to some device types failed.

Note that unlike the framework's HttpWebResponse class etc, which signals an error by throwing a WebException, the ObexWebRequest class signals an error by returning an error status code in ObexWebResponse.StatusCode. Status code BadRequest indicates an error at connect time, in the network connection, the OBEX connection or even in the format or content of the URI. Status code InternalServerError indicates an error during the transfer. The new ObexWebRequest2 class behaves like the framework classes, throwing a WebException and it includes the original error as the InnerException property.

Use code like the following to send a file.

CopyC#

' The host part of the URI is the device address, e.g. IrDAAddress.ToString(),
' and the file part is the OBEX object name.
Dim uri As New Uri("obex://112233445566/HelloWorld.txt")
Dim req As New ObexWebRequest(uri)
req.ReadFile("Hello World.txt")
Dim rsp As ObexWebResponse = CType(req.GetResponse(),ObexWebResponse)
Console.WriteLine("Response Code: {0} (0x{0:X})", rsp.StatusCode)

Or, to send locally generated content use something like the following.

CopyC#

' The host part of the URI is the device address, e.g. IrDAAddress.ToString(),
' and the file part is the OBEX object name.
Dim uri As New Uri("obex://112233445566/HelloWorld2.txt")
Dim req As New ObexWebRequest(uri)
Using content As Stream = req.GetRequestStream()
   ' Using a StreamWriter to write text to the stream...
   Using wtr As New StreamWriter(content)
      wtr.WriteLine("Hello World GetRequestStream")
      wtr.WriteLine("Hello World GetRequestStream 2")
      wtr.Flush()
      ' Set the Length header value
      req.ContentLength = content.Length
   End Using
   ' In this case closing the StreamWriter also closed the Stream, but ...
End Using
Dim rsp As ObexWebResponse = CType(req.GetResponse(),ObexWebResponse) 
Console.WriteLine("Response Code: {0} (0x{0:X})", rsp.StatusCode)

See also the ObexPushApplication and ObexPushVB sample programs.