uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ComCtrls,  Buttons, ExtCtrls;procedure Tab( var Key: Char);
begin
    if key=#13 then   {   判断是按执行键}  
    Begin    
        key:=#0;
        perform(WM_NEXTDLGCTL,0,0);{移动到下一个控件}  
    end   
end;