procedure
TForm1.Button1Click(Sender: TObject);//На русский
var
Layout: array[0.. KL_NAMELENGTH] of char;
begin
LoadKeyboardLayout( StrCopy(Layout,'00000419'),KLF_ACTIVATE);
end;
procedure
TForm1.Button2Click(Sender: TObject);//На английский
var
Layout: array[0.. KL_NAMELENGTH] of char;
begin
LoadKeyboardLayout(StrCopy(Layout,'00000409'),KLF_ACTIVATE);
end;
Взято
из http://forum.sources.ru