Example of using attachments to the browser?

[PDVD]

Hi,

Using SharpMimeTools, and it works fine!

The only problem i'm faceing is 'streaming' attachments to the browser...

I have this ASP.NET (VB.NET) code:

   Dim Buffer(attachment.Stream.Length) As Byte
   attachment.Stream.Read(Buffer, 0, CInt(attachment.Stream.Length))
   attachment.Stream.Close()
   Response.ContentType = "image/jpeg" 'I know this to be a jpg file...
   Response.BinaryWrite(Buffer)

But this does not give me a valid image file... (if I try with a plain text attachment file, it won't work either)

Anybody have a example somewhere?

[Matt Drechsler]

Sure I'm replying to a 2 year old message, and to an empty forum, but what have I got to lose?

I echo the sentiment of not being able to stream attachments, but in my case to a database, not directly to a web page.  It simply populates my BLOB with zeroes, padded to the correct size, UNLESS I use attachment.save first.   Is the .stream availability tied to .save ing first?  Is there a way to make it available without saving?

Here is a snippet of my "working example":

            If message.Attachments IsNot Nothing Then
                For Each attachment As anmar.SharpMimeTools.SharpAttachment In message.Attachments
                    attachment.Save("C:\temp\", True)
                    Dim Buffer(attachment.Stream.Length) As Byte
                    attachment.Stream.Read(Buffer, 0, CInt(attachment.Stream.Length))
                    attachment.Stream.Close()
                    InsertAttachment(id, [Enum].GetName(GetType(MimeTopLevelMediaType), attachment.MimeTopLevelMediaType) & "/" & attachment.MimeMediaSubType, attachment.Name,  Buffer))
                Next
            End If

[Angel Marin]

What's the exact SharpMessage constructor you're using?

I'm guessing some code paths are leaving the stream in undesired states, and doing a .Save accidentally resets it to a usable state.

[Angel Marin]

I've commited a fix to svn that might be the cause to this. Can you give it a try?

[Matt Drechsler]

Angel, the quick is response is much appreciated.

Here is the code I am using to construct SharpMessage

    Private Sub InsertMessage(ByVal messageText As String)
        Dim message As New SharpMessage(messageText)

I've had to give myself a crash course on building a dll in Visual Studio using your code, and after tracking down a few of the "gotchyas", most of which are already solved in this forum, I got one built and was able to test it.  I still get zeros.

It is interesting being able to step through the C# code behind the DLL now in the Visual Studio debugger.  I can see that _stream is null, and so the code in SharpMessage.cs that checks for this then dumps into
    else if ( this._saved_file!=null )
        return this._saved_file.OpenRead();

so that's why it works if I've saved the file.

Am I missing something simple?  Why is _stream null?

Feel free to call me a dunce and point out my silly mistake. :)

[Angel Marin]

If this._stream is null once you've saved the file and that's ok, in-memory stream is closed once the file is already in filesystem. It's shouldn't be null before calling .Save and it's .Position should be 0 though.

I haven't been able to reproduce this … what's the value of attachment.Stream.Position before calling Read (and without calling .Save)?

[Matt Drechsler]

OK, I must have still had some debugging code in place from before I recompiled the DLL.
All is working now!

Just for completeness, to answer your question, the value of attachment.Stream.Position is 0 now before the Read, and equal to the Length immediately after.

Is there any chance to get an updated binary posted?  I'm not sure I trust the kludgy hacks I had to perform to get the code to compile in VS. :)

Thanks for the learning experience and again, your very quick response.

-=Matt

[Angel Marin]

Glad to hear it's working now.

I'll try to get around to finally do a new binary release …

BTW, you're better off using that svn compiled code than the last binary release, there has been like a zillion bug fixes since that release …