QString str = ui.ll->text();	try	{		if (str == NULL)		{			throw 1;		}		else		{			throw 1.2;		}	}	catch (int & e)                                                                        //参数的类型要与throw中类型保持一致，才能捕捉到；加上&能捕捉到抛出的值	{		if (e == 1)		{			ui.ll->setText("68 04 00 43 00 00 00");		}		qDebug()<
     
      setText("1.2");		}		qDebug()<
      
       setText("...");	}