How to pull jpg from a Blob Field in Delphi and display in a TImage?

Question

I have the following code, but it doesn't display the jpg in the TImage:

  sf := TfrmSplash.Create(nil);
  ms := TMemoryStream.Create;
  try
    bf := TBlobField(dbfuncs.tblBlobs.FieldByName('BBlob'));
    bf.SaveToStream(ms);
    ms.Position := 0;
    sf.imgDisplay.Picture.Graphic.LoadFromStream(ms);
    sf.Show;
    Sleep(2000);
  finally
    ms.Free;
    sf.Free;
  end;

Why doesn't this work? I have jpeg in the uses clause of both forms involved. But nothing is displayed in the image.....

See also [saving and loading image with ADO](http://stackoverflow.com/a/11775398/757830) — NGLN, Aug 15 '12 at 19:46

score 2 · Accepted Answer · answered Oct 21 '10 at 13:35

2

Don't you have to stream it into a TJPEG first, then assign that into the TImage? I don't have code handy here (though can dig it out later) but when I've done this in the past I'm pretty sure I have to do something like

MyJPeg.LoadFromStream

followed by

MyPicture.Graphic.Bitmap.Assign(MyJPeg)...?

answered Oct 21 '10 at 13:35

robsoft

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Ok - I just tried that, but no go. The jpg still doesn't appear in the TImage.... – croceldon Oct 21 '10 at 13:50
is there anything unusual about the TImage - are you creating it dynamically or is it an on-form component? Just wondering if there's a handle/parent problem. Can you temporarily hack your code to load a *bitmap* from a local file, just to test that the TImage will definitely show a graphic? Sorry if you've already tried/considered that! – robsoft Oct 21 '10 at 14:03
rob, you're on to something - it's not displaying a bmp file that I know is good. But I don't know why, it's just a standard TImage component.... – croceldon Oct 21 '10 at 14:11
If I switch to a ShowModal for the form, it shows the bmp file – croceldon Oct 21 '10 at 14:14
Try a sf.imgDisplay.Refresh just after the show, it might simply be that it's not getting a chance to repaint the window. – robsoft Oct 21 '10 at 14:16

score 2 · Answer 2 · edited Aug 15 '12 at 18:22

2

uses
   ... DB;

TBlobField(dbfuncs.tblBlobs.FieldByName('BBlob')).LoadFromFile('file name');
TBlobField(dbfuncs.tblBlobs.FieldByName('BBlob')).LoadFromStream();

edited Aug 15 '12 at 18:22

Remy Lebeau

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answered Oct 21 '10 at 14:39

NMD

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How to pull jpg from a Blob Field in Delphi and display in a TImage?

2 Answers2

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