TImage inside TComponent serializaton

[isola 1]

I have a class that is inherited from TComponent.
The class have some published fields.

It is possible in runtime using the bundle below save the class to a file.

MemStream.WriteComponent(self);
FileStream := TFileStream.Create(FStorageName, fmCreate);
ObjectBinaryToText(MemStream, FileStream);

Then it's possible using below code to read saved data back into an object directly.

ObjectTextToBinary(FileStream, MemStream);

 

 

Everything works well for simple types(Int, string, boolean).
This serialization works as well for some other types (TStringList, TCollection).

What about TImage class?
It seems published TImage is ignored.
But TImage is also the descendant of TComponent. 

Does Delphi use the same approach to save TForm to dfm-files?
Whether any extra effort should be made to serialize TImage?

[Uwe Raabe 1890]

Make the Owner of that TImage instance your component and set csSubComponent in the TImages ComponentStyle.

 

That means, the image should be created like this:

FImage := TImage.Create(Self);
FImage.SetSubComponent(True);

 

[programmerdelphi2k 235]

1 hour ago, isola said:

Does Delphi use the same approach to save TForm to dfm-files

or more simple way;

• you can use only "Memory streams instead save on file"

procedure TForm1.Button1Click(Sender: TObject);
var
  LMemStream: TMemoryStream;
  LStrStream: TStringStream;
begin
  LMemStream := TMemoryStream.Create;
  try
    LMemStream.WriteComponent(Image1);
    LMemStream.SaveToFile('myTImage.bin');
    //
    LStrStream := TStringStream.Create;
    try
      LMemStream.Position := 0;
      ObjectBinaryToText(LMemStream, LStrStream);
      LStrStream.Position := 0;
      Memo1.Text          := LStrStream.DataString;  // showing the propers
    finally
      LStrStream.Free;
    end;
    //
    Image1.Picture.Bitmap := nil; // just for test...
  finally
    LMemStream.Free;
  end;
end;

procedure TForm1.Button2Click(Sender: TObject);
var
  LMemStream: TMemoryStream;
begin
  LMemStream := TMemoryStream.Create;
  try
    LMemStream.LoadFromFile('myTImage.bin');
    LMemStream.ReadComponent(Image1);
  finally
    LMemStream.Free;
  end;
end;

 

Edited July 1, 2023 by programmerdelphi2k

[programmerdelphi2k 235]

...

Edited July 1, 2023 by programmerdelphi2k

[isola 1]

FImage := TImage.Create(Self);
FImage.SetSubComponent(True);

It works.
Uwe Raabe, thank you very much!