参考博客:qt中常用lambda表达式_夏有凉风,冬有雪的博客-CSDN博客_qt lambda
1、无参数写法(信号槽)
connect(ui->pushButton,&QPushButton::clicked,[=](){ qDebug()<<"2222222"; qDebug()<<u8"你好"; });
2、带参数写法
connect(this,&lambdaTest::testSingal,this,[=](QString path){ qDebug()<<path; });