Example of PictureStream request

[EvP]

Hi, i'm trying to put a picture from a database into a report using PictureStream.

I went through the reference manual but I can't get it to work, and the manual is pretty unclear to me about this.

I'm using Delphi and VPE Professional version 6

I came this far, no clue if i'm barking up the wrong tree or that's it's just a minor problem.

(this is not the actual code, it's just an example i tried to create)

Can you help me out ?


Procedure ImagePrint;

var

Blob : Tstream;
PictureStream : VPEStream;
VertPos : Double; // vertical position
Buffer : Tbytes;


begin
VertPos := 0.5;

Report.OpenDoc;
Report.License('VPE-xxxxx-xxxx', 'xxxx-xxxx'); // enable license

PictureStream := Report.CreateMemoryStream(64000); // picture should fit in 64k

Data.dbImage.First; // go to first record of database
while not Data.dbImage.Eof do // until end reached
begin
// fill the blob with the Picture;
Blob := Data.dbImage.CreateBlobStream(Data.dbImage.FieldByName('PICTURE'), bmread);

// ... problem code starts here

SetLength(Buffer, Blob.Size);
Blob.Read(Buffer, Blob.size);
PictureStream.Write(Buffer,Blob.Size);

// ... problem code ends here

// Put the picture in the document and give it the ID of the picture
Report.PictureStream(PictureStream,1,VertPos,6,VertPos+5,data.dbImage.FieldValues['CATID']);

VertPos := VerPos + 6;

end;

Report.Preview;


end;



Kind regards, Erik van Putten

[IDEAL Software Support]

You should check the property LastError after calling the VPE API in order to find out where the problem is.

From a rough view at your code, it seems there is a call to Seek(0) missing:

Code: Select all

PictureStream.Write(Buffer,Blob.Size);
==>PictureStream.Seek(0)

After you have written the blob to the VPE memory stream, the internal file pointer of the VPE memory stream needs to be reset to the beginning, because the following call to PictureStream() will read from the current stream position. There is sample source code for Delphi shipped with VPE, where this is demonstrated.