Clone Delphi Component - delphi

Question

I have X (more than 1) comboboxes declared on a form. (Designtime)
All these comboboxes have the same properties (except position, handle, and a few others they can't share)
I would to give them all the same behavior during runtime, which means if e.g. I add/delete an item or change the ItemIndex or stuff like that, then all comboboxes should do the same.
How can I "clone" all properties/events/etc. from one component at runtime to X other components without doing an operation over and over again for each component?

Answer 1

You can use ReadComponent and WriteComponent from TStream too.
procedure TForm1.Button1Click(Sender: TObject);
var
oStream: TMemoryStream;
i: integer;
cbCombos: array[0..4] of TComboBox;
begin
oStream := TMemoryStream.Create;
ComboBox1.Tag := '666'; { \m/ }
try
oStream.WriteComponent(ComboBox1);
for i := 0 to 4 do
begin
cbCombos[i] := TComboBox.CreateParented(Self.Handle);
oStream.Position := 0;
oStream.ReadComponent(cbCombos[i]);
cbCombos[i].Name := 'AnotherComboBox' + IntToStr(i+1);
cbCombos[i].Parent := Self;
cbCombos[i].Tag := cbCombos[i].Tag + i + 1;
cbCombos[i].Left := 16;
cbCombos[i].Top := 36 * (i + 2);
cbCombos[i].OnMouseEnter := ComboBox1MouseEnter;
end;
finally
FreeAndNil(oStream);
end;
end;
procedure TForm1.ComboBox1MouseEnter(Sender: TObject);
begin
TWinControl(Sender).Hint := IntToStr(TWinControl(Sender).Tag);
end;

Answer 2

You can do that via Extended RTTI
This is a start - by no means complete:
procedure TForm62.CloneComponent(const aSource, aDestination: TComponent);
var
ctx: TRttiContext;
RttiType, DestType: TRttiType;
RttiProperty: TRttiProperty;
Buffer: TStringlist;
begin
if aSource.ClassType <> aDestination.ClassType then
raise Exception.Create('Source and destiantion must be the same class');
Buffer := TStringlist.Create;
try
Buffer.Sorted := True;
Buffer.Add('Name');
Buffer.Add('Handle');
RttiType := ctx.GetType(aSource.ClassType);
DestType := ctx.GetType(aDestination.ClassType);
for RttiProperty in RttiType.GetProperties do
begin
if not RttiProperty.IsWritable then
continue;
if Buffer.IndexOf(RttiProperty.Name) >= 0 then
continue;
DestType.GetProperty(RttiProperty.Name).SetValue(aDestination, RttiProperty.GetValue(aSource));
end;
finally
Buffer.Free;
end;
end;