如何在程序中控制某个控件的一个事件的有效及无效？

Question

Button1.OnClick := nil <--------- DisabledButton1.OnClick := OnClick; <---------- Enabled

Answer 1

Button1.OnClick:=nil;
在需要時﹐又可把其句柄取回來﹕
Button1.OnClick := MyClick;如果不怕麻煩﹐就自己寫個組件吧﹐你想咋辦就咋辦﹗

Answer 2

procedure TForm1.Button1Click(Sender: TObject);
begin
  Button2.OnClick := nil; //无笑
  Button2.OnClick := Button2Click; //有笑
end;

Answer 3

比如说对某个按钮的点击事件，先把你要做的操作写成一个方法
然后
  Button1OnClick := @YourProcedureName;
就是有效
  Button1OnClick := nil;
就是无效

Answer 4

procedure TForm1.Button1Click(Sender: TObject);
begin
  Button2.OnClick := nil; //无笑
  Button2.OnClick := Button2Click; //有笑
end;

Answer 5

unit Unit1;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;type
  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;var
  Form1: TForm1;implementation{$R *.dfm}procedure TForm1.Button1Click(Sender: TObject);
begin
    showmessage('dd');
end;procedure TForm1.Button2Click(Sender: TObject);
begin
    button1.OnClick:=nil;
end;procedure TForm1.Button3Click(Sender: TObject);
begin
    button1.OnClick:=button1click;
end;end.

Answer 6

unit Unit1;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;type
  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;var
  Form1: TForm1;implementation{$R *.dfm}procedure TForm1.Button1Click(Sender: TObject);
begin
    showmessage('dd');
end;procedure TForm1.Button2Click(Sender: TObject);
begin
    button1.OnClick:=nil;
end;procedure TForm1.Button3Click(Sender: TObject);
begin
    button1.OnClick:=button1click;
end;end.