delphi VCL组件同名继承

当我们在扩展一个 vcl 组件功能的时候，既想保留IDE中能拖动大小与直接设置属性的功能，又想减少写创建与释放代码和安装扩展后新组件的麻烦，那么本文中的方法，就非常实用了。

以给TStringGrid的单元格加上颜色功能为例，先看如何调用:

unit Unit1;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,
  System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Vcl.Grids, uColorGrid;

type

  TStringGrid = class(uColorGrid.TStringGrid); // 此句必备！

  TForm1 = class(TForm)
    StringGrid1: TStringGrid;
    Button1: TButton;
    Button2: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}
{ TStringGrid }

procedure TForm1.Button1Click(Sender: TObject);
var
  c: TCellColor;
begin

  // 设置颜色要在改变表格的行列数之后

  c.TextColor := clblue;
  c.BackGroundColor := clyellow;

  StringGrid1.cells[2, 1] := 'blue';
  StringGrid1.CellsColor[2, 1] := c;

  c.TextColor := clred;
  c.BackGroundColor := clgreen;
  StringGrid1.cells[3, 1] := 'red';
  StringGrid1.CellsColor[3, 1] := c;

  c.TextColor := clgray;
  c.BackGroundColor := clnavy;

  StringGrid1.cells[4, 1] := 'yellow';
  StringGrid1.CellsColor[4, 1] := c;

end;

procedure TForm1.Button2Click(Sender: TObject);
var
  c: TCellColor;
begin

  c.TextColor := clred;
  c.BackGroundColor := clolive;

  StringGrid1.cells[2, 1] := 'blue';
  StringGrid1.CellsColor[2, 1] := c;

  c.TextColor := clblue;

  c.BackGroundColor := clMaroon;
  StringGrid1.cells[3, 1] := 'red';
  StringGrid1.CellsColor[3, 1] := c;

  c.TextColor := clgray;
  c.BackGroundColor := clLime;
  StringGrid1.cells[4, 1] := 'yellow';
  StringGrid1.CellsColor[4, 1] := c;

end;

end.

unit1.pas