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Summary
Receive the contents or filename of the extracted message body and any attachments.
Description
The OnRecvBody event occurs in response to calling the ExtractMessageEnd method. This
event will occur during the extract message process to deliver the contents or filename of
the message. It will also occur to deliver the file content or filename of any attachments
the message may have.
The MIME ActiveX control will first extract the message header and body. The Mime
ActiveX control fires the OnRecvHeader event to set the message properties. The body will
be saved to the Destination directory (set in the call to the ExtractMessageStart method)
and the OnRecvBody event will be fired to deliver the file name. If the Destination was
set to NULL the MIME ActiveX control will then deliver the message by firing the
OnRecvBody event one or more times to deliver the contents of the message body. The MIME
ActiveX control will then similiarly fire the OnRecvHeader and OnRecvBody events to
deliver any extracted attachments.
The Buffer parameter will contain the data or the filename, and Length
will be set to the length of buffer. The IsFile parameter specifies whether a
filename, or file contents is being delivered. If IsFile is 0 then the actual
content of the message or attachment is being delivered; otherwise if IsFile is 1
the name of the file that contains the message or attachment is being delivered by this
event.
To abort the extract message, set the Action property to ACTION_ABORT (or call the
Abort method) during this event. The action in progress will be canceled and no further
such events will occur.
Technical Note
If the message to be extracted is of type multipart or
"message/external-body" the sequence of the OnRecvHeader and OnRecvBody events
may differ. In case of multipart messages a OnRecvHeader event can be followed by another
OnRecvHeader event instead of a OnRecvBody event. After MIME ActiveX control fires the
OnRecvHeader event with the initial header, the sequence will be OnRecvHeader event
followed by an OnRecvBody event unless there is a part with no body or if there is a
nested multipart in which case an OnRecvHeader event may be followed by another
OnRecvHeader event. The first body part is usually treated as the message body. The
extraction of the rest of the body parts will follow same sequence. The MIME ActiveX
control will automatically decode any encoded body part.
Similarly if the message is of type message/external-body then the initial OnRecvHeader
event will be followed by an OnRecvHeader event instead of an OnRecvBody event.
Note that the general sequence of upcalls will be OnRecvHeader event followed by an
OnRecvBody event unless there is a part with no header or an empty body, in those special
cases a OnRecvHeader event may be followed by another OnRecvHeader event or a OnRecvBody
event may be followed by another OnRecvBody event. It is the application's responsibility
to keep track of, and decide how to treat the data received in each OnRecvBody event. The
application can so this by checking the ContentType property after each OnRecvHeader
event.
If the message is a non-MIME message then the attachments will be extracted and the
MIME ActiveX control will fire the OnRecvHeader event followed by the OnRecvBody event.
Note that for non-MIME messages only the Encoding and the Filename properties will
be set by the OnRecvHeader event.
For non_ MIME messages, the attachment files that are not uuencoded will have a .TXT
extension and the uuencoded files will be renamed to their original names after they are
uudecoded. If renaming fails then the uudecoded file will have either a .ATF or .UUE
extension.
For MIME messages, the MIME ActiveX control will first try to find the name of the
attached file in the header. If there is one then the attachment file is given that name.
If the filename does not exist, or if there already exists a file with the same name, then
the file will have some temporary name, the application can check the FileName property to
find the suggested name of the attachment file.
A file encoded in binhex40 generally has two parts, data fork and resource fork. The
MIME ActiveX control will first decode the data fork and fire the OnRecvBody event (the Length
parameter of will be set to 0 to indicate the end of data fork), then the resource fork,
if present, will be decoded and delivered with OnRecvBody event.
If the message is a partial message then the MIME ActiveX control will only fire the
OnRecvHeader and OnRecvBody events when it receives the reassembled entire message.
Example
' HeaderInfo is a structure for the attachment name, encoding used and the
content type
' see the MIME sample for the definition
Sub Mime_OnRecvBody (Buffer As String, Length As Integer, IsFile
As Integer)
' receive message body
If MsgBodyDone = False Then
If (Buffer = "")
MsgBodyDone = True
Else If (IsFile = 0) Then
Message = Buffer
Else
Message = "Message File: " & Buffer & Chr(10)
End If
' display message
MsgBox Message, 64, "Sample Program"
Exit Sub
End If
' send attachment filename
If AttachDone = False Then
If Buffer = "" Then
AttachDone = True
Else If (IsFile = 0) Then
Message = Buffer
Else
Message = "Attachment Received: " & Buffer & Chr(10)
End If
' display message
MsgBox Message, 64, "Sample Program"
Exit Sub
End If
' display message
MsgBox Message, 64, "Sample Program"
End Sub
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