简单剖析⼀下：connect，可以信号---槽，信号---信号qt4.x,实际上⽤的是SIGNAL，SLOT这两个宏
[static] QObject::connect(const *sender, const char *signal, const *receiver, const char *method, type = Qt::AutoConnection)
connect返回bool判断是否连接成功 qt5.x
[static] QObject::connect(const *sender, PointerToMemberFunction signal, const *receiver, PointerToMemberFunction method, type =Qt::AutoConnection)连接过程中connect⾃⾏判断 拓展：
若槽实现⽐较简单可以使⽤匿名函数lambda实现
::connect(lineEdit, &::textChanged, [=](QString data){ if(!data.isEmpty())
qDebug()< connect(sendBtn,&QPushButton::clicked, [=](){ qDebug()<<\"123\"< 因篇幅问题不能全部显示，请点此查看更多更全内容