weather station
the QUdpSocket class provides a UDP socket.
UDP (User Datagram Protocol) is a lightweight, unreliable, datagram-oriented, connectionless protocol. It can be
//用户数据协议是一个轻量，不可靠，数据报式的 ,无连接的协议
used when reliability isn’t important. QUdpSocket is a subclass of QAbstractSocket that allows you to send and receive UDP datagrams.
//当连接是不重要时可以使用，QUdpSocket是QAbstractSocket的子类，允许发送和接收udp数据报
bool QUdpSocket::bind(const QHostAddress & address, quint16 port)
Binds this socket to the address address and the port port. When bound, the signal readyRead()
//绑定socket到地址和端口，绑定时，当udp数据报到指定地址和端口时，信号readyRead发射，
is emitted whenever a UDP datagram arrives on the specified address and port. This function is useful to write UDP servers.
bool QUdpSocket::hasPendingDatagrams() const
Returns true if at least one datagram is waiting to be read; otherwise returns false.
//当至少有一个数据报在等待读时 会返回真，否则返回错误
weather ballon
qint64 QUdpSocket::writeDatagram(const char * data, qint64 size, const QHostAddress & address, quint16 port)
Sends the datagram at data of size size to the host address address at port port. Returns the number of bytes sent on success;
//在port发送指定大小的数据报到host，返回成功发送的字节数
otherwise returns -1.