Question

我正在使用QUdpSocket来从服务器接收数据。当我收到数据时，SFML可以正常工作，我可以通过SocketUdp接收数据但是使用qt它不起作用。

void TheClass::Bind()
{
  m_sock_receive = new QUdpSocket(this);
  if (m_sock_receive->bind(QHostAddress::Any, port))
  {
    std::cout << "Bind: OK" << std::endl;
    connect(m_sock_receive, SIGNAL(readyRead()), this, SLOT(QtReceive()));
  } 
  else
      std::cout << "Bind: NOK" << std::endl;
}

void TheClass::QtReceive()
{
    std::cout << "Pending data !" << std::endl;
}

Answer 1

我会在绑定之前进行连接。绑定后，readyRead可能会在连接调用完成之前触发。如果您没有清空待处理的数据报，则readyRead将不会再次触发。

Answer 2

为了将SIGNAL（readyRead（））连接到任何槽，QUdpSocket必须位于QAbstractSocket :: BoundState中。虽然在连接之前调用bind，但是QUdpSocket上的绑定会进行非阻塞调用，这意味着绑定可能会被延迟。要确保在绑定完成并且QUdpSocket处于绑定状态后将SIGNAL（readyRead（））连接到SLOT（QtReceive（）），请执行以下操作：

void TheClass::Bind()
{
  m_sock_receive = new QUdpSocket(this);
  connect(m_sock_receive, SIGNAL(stateChanged(QAbstractSocket::SocketState)),
        this, SLOT(onSocketStateChange(QAbstractSocket::SocketState)));
  if (m_sock_receive->bind(QHostAddress::Any, port))
  {
    std::cout << "Bind: OK" << std::endl;
  } 
  else
      std::cout << "Bind: NOK" << std::endl;
}

void TheClass::QtReceive()
{
    std::cout << "Pending data !" << std::endl;
}

void TheClass::onSocketStateChange (QAbstractSocket::SocketState state) {
    if ( state == QAbstractSocket::BoundState ) {
        connect(m_sock_receive, SIGNAL(readyRead()), this, SLOT(QtReceive()));
    }
}

QUdpSocket：无法接收数据报

2 个答案: