procedure TForm1.DBGrid1DrawColumnCell(Sender: TObject; const Rect: TRect;
DataCol: Integer; Column: TColumn; State: TGridDrawState);
begin
if gdfocused in state then
begin
if column.FieldName='xxx' then //xxx为你要让combobox显示的那列的字段名
begin
ComboBox1.Left:=rect.Left+form1.DBGrid1.Left;
ComboBox1.Top:=rect.Top+form1.DBGrid1.Top;
ComboBox1.Width:=rect.Right-rect.Left;
ComboBox1.Height:=rect.Bottom-rect.Top;
ComboBox1.Visible:=true;
end;
end;
end;