procedure TForm_main.N24Click(Sender: TObject);
var ppchar;
begin
try
begin
pp:=Pchar(ExtractFilePath(Application.exeName)+'系统帮助手册.chm');
Shellexecute(handle,'open',pp,nil,nil,SW_SHOWNORMAL);
end;
except
Application.MessageBox('系统提示:没有找到相应的目录或帮助文件!','系统提示...',MB_OK+MB_ICONINFORMATION);
end;
end;