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Delphi 拦截Tab按键消息

作者:admin 来源: 日期:2019/10/10 21:48:23 人气: 标签:

 
如果要拦截TAB键行为,应该捕获 CM_DIALOGKEY 消息。在这里示例中,如果将 YouWantToInterceptTab 布尔值设置为 true,则将会吃掉 TAB 键:


unit Unit1;
interface
uses
 Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
 Dialogs, StdCtrls;
type
    TForm1 = class(TForm)
        private
        YouWantToInterceptTab: Boolean;
        procedure CMDialogKey(var AMessage: TCMDialogKey); message CM_DIALOGKEY;
        public
        { Public declarations }
    end;
var
 Form1: TForm1;
implementation
{$R *.dfm}
procedure TForm1.CMDialogKey(var AMessage: TCMDialogKey);
begin
 if AMessage.CharCode = VK_TAB then
 begin
    ShowMessage('TAB key has been pressed in ' + ActiveControl.Name);
    if YouWantToInterceptTab then
    begin
        ShowMessage('TAB key will be eaten');
        AMessage.Result := 1;
    end
    else
        inherited; 
        end
        else
        inherited;
    end;
end.