現(xiàn)UDP單播、組播和廣播功能)
一、UDP單播、廣播和組播的說(shuō)明UDP是不可靠、無(wú)連接的所以劃分為發(fā)送方和接收方更好理解1、單播UDP是無(wú)連接的進(jìn)行單播通信時(shí)必須要綁定接收方端口發(fā)送方直接通過(guò)接收方的ip和綁定的端口進(jìn)行通信。發(fā)送方可以綁定端口也可以不用綁定端口不綁定端口的話系統(tǒng)會(huì)隨機(jī)分配端口。對(duì)于多網(wǎng)卡來(lái)說(shuō)需要指定網(wǎng)卡綁定一個(gè)網(wǎng)卡的ip。如果不進(jìn)行顯式的綁定操作QUdpSocket對(duì)象將會(huì)使用默認(rèn)的綁定方式自動(dòng)選擇一個(gè)可用的 ip 地址進(jìn)行綁定。2、廣播對(duì)于只有1個(gè)網(wǎng)卡的主機(jī)來(lái)說(shuō)可以不用顯示綁定ip發(fā)送方直接發(fā)送廣播就行接收方綁定廣播端口就行這樣才能看到收到的消息。對(duì)于多網(wǎng)卡來(lái)說(shuō)要指定唯一的網(wǎng)卡ip并且在廣播前要綁定廣播端口。ip可以不用綁定這樣系統(tǒng)會(huì)隨機(jī)分配一個(gè)網(wǎng)卡ip。3、組播對(duì)于只有1個(gè)網(wǎng)卡的主機(jī)來(lái)說(shuō)可以不用綁定ip直接綁定端口后加入組播就行。系統(tǒng)分配任意一個(gè)ip 相當(dāng)于QHostAddress::AnyIPv4。對(duì)于多網(wǎng)卡來(lái)說(shuō)要指定唯一的網(wǎng)卡并且在加入組播前要綁定組播端口ip可以不用綁定系統(tǒng)分配任意一個(gè)ip。注意指定網(wǎng)卡不等于指定ip1、使用setMulticastInterface方法可以指定一個(gè)明確的網(wǎng)卡但并不意味著只有一個(gè) IP 地址。一個(gè)網(wǎng)卡可以綁定多個(gè) IP 地址例如在同一臺(tái)主機(jī)上同時(shí)存在有線網(wǎng)卡和無(wú)線網(wǎng)卡它們可能都連接到同一局域網(wǎng)并分別配置了不同的 IP 地址。此時(shí)通過(guò)setMulticastInterface方法指定了一個(gè)明確的網(wǎng)卡后并不確定使用哪個(gè) IP 地址來(lái)進(jìn)行組播通信。如果需要確保使用特定的 IP 地址進(jìn)行組播通信則需要使用bind方法來(lái)將QUdpSocket對(duì)象綁定到具體的 IP 地址和端口上這樣每次進(jìn)行組播通信時(shí)都會(huì)使用該 IP 地址來(lái)發(fā)送和接收數(shù)據(jù)報(bào)文。2、使用QHostAddress::AnyIPv4參數(shù)可以將QUdpSocket對(duì)象綁定到本機(jī)的所有 IPv4 地址。這意味著該QUdpSocket對(duì)象可以接收通過(guò)本機(jī)的任意一個(gè) IPv4 地址發(fā)送到指定端口的數(shù)據(jù)包。然而需要注意的是綁定到多個(gè) IPv4 地址并不意味著可以同時(shí)從多個(gè)地址接收數(shù)據(jù)包。在任何給定的時(shí)刻QUdpSocket對(duì)象只能通過(guò)一個(gè) IP 地址接收數(shù)據(jù)包。當(dāng)有多個(gè) IPv4 地址可用時(shí)QUdpSocket對(duì)象會(huì)選擇其中一個(gè)地址來(lái)接收數(shù)據(jù)包。這個(gè)選擇通常由操作系統(tǒng)或網(wǎng)絡(luò)棧決定并且可能會(huì)受到各種因素的影響例如網(wǎng)絡(luò)接口的優(yōu)先級(jí)、路由表等。因此使用QHostAddress::AnyIPv4參數(shù)可以讓QUdpSocket對(duì)象綁定到本機(jī)的所有 IPv4 地址但實(shí)際上它只能通過(guò)其中一個(gè)地址接收數(shù)據(jù)包。具體使用哪個(gè)地址取決于操作系統(tǒng)和網(wǎng)絡(luò)環(huán)境。二、遇到的UDP通信的問(wèn)題參考查看所有端口netstat -ano查看某個(gè)端口netstat -ano | findstr 端口號(hào)查看TCP的socket信息netstat -an | find TCP查看UDP的socket信息netstat -an | find UDP關(guān)于QT UDP組播的幾個(gè)問(wèn)題https://blog.csdn.net/tom06/article/details/52163665?spm1001.2014.3001.5506UDP多播/組播通信同一局域網(wǎng)下的兩臺(tái)機(jī)器通信接收不到數(shù)據(jù)https://blog.csdn.net/qq_43290013/article/details/117288296?spm1001.2014.3001.5506QT讀取網(wǎng)卡列表多網(wǎng)卡綁定組播網(wǎng)卡https://blog.csdn.net/qq_30727593/article/details/127441711?spm1001.2014.3001.5506三、效果與代碼1、在.pro文件中添加如下內(nèi)容QT network2、在.h文件中添加串口所用的頭文件#include QUdpSocket #include QNetworkInterface3、添加一個(gè)QUdpSocket* socket的類成員并在.cpp中實(shí)例化對(duì)象socket new QUdpSocket;4、掃描可用網(wǎng)口QListQNetworkInterface interfaceList QNetworkInterface::allInterfaces(); foreach (QNetworkInterface nif, interfaceList) { // 檢查網(wǎng)卡是否有效并已經(jīng)啟用 if (nif.isValid() nif.flags().testFlag(QNetworkInterface::IsUp)) { // 將已經(jīng)啟用的網(wǎng)卡名稱添加到列表中 enabledInterfaceList.append(nif); QListQNetworkAddressEntry entries nif.addressEntries(); foreach (QNetworkAddressEntry entry, entries) { if (entry.ip().protocol() QAbstractSocket::IPv4Protocol) { if(entry.ip().toString() localIP){ index; }; } } } }5、對(duì)組播進(jìn)行設(shè)置可以忽略//組播的數(shù)據(jù)的生存期數(shù)據(jù)報(bào)沒(méi)跨1個(gè)路由就會(huì)減1.表示多播數(shù)據(jù)報(bào)只能在同一路由下的局域網(wǎng)內(nèi)傳播 socket-setSocketOption(QAbstractSocket::MulticastTtlOption,1); //1是允許loopback模式自發(fā)自收,0是阻止。 socket-setSocketOption(QAbstractSocket::MulticastLoopbackOption, true);6、初始化組播設(shè)置int MainWindow::init_group(QUdpSocket *socket, QNetworkInterface currentInterface, QHostAddress localAddress, QHostAddress targetAddress, int localPort) { if (targetAddress.isMulticast()) {//isMulticast()判斷是否是組播地址 if (localPort 0) {//判斷是否指定本地端口 //bind(localAddress, QUdpSocket::ShareAddress | QUdpSocket::ReuseAddressHint)可以換成bind(QHostAddress::AnyIPv4, QUdpSocket::ShareAddress | QUdpSocket::ReuseAddressHint) if (socket-bind(localAddress, QUdpSocket::ShareAddress | QUdpSocket::ReuseAddressHint)) { socket-setMulticastInterface(currentInterface); if (socket-joinMulticastGroup(targetAddress, currentInterface)) { qDebug() 未指定本地端口,加入組播成功; return 1; } else { qDebug() 未指定本地端口,加入組播失敗; return -1; } } else { qDebug() 未指定本地端口,綁定失敗; return -1; } } else { if (socket-bind(localAddress, localPort, QUdpSocket::ShareAddress | QUdpSocket::ReuseAddressHint)) { socket-setMulticastInterface(currentInterface); if (socket-joinMulticastGroup(targetAddress, currentInterface)) { qDebug() 指定本地端口,加入組播成功; return 1; } else { qDebug() 指定本地端口,加入組播失敗; return -1; } } else { qDebug() 指定本地端口,綁定失敗; return -1; } } } else { qDebug() 目標(biāo)地址不是組播地址; return -1; } // 如果執(zhí)行到這里說(shuō)明沒(méi)有通過(guò)任何返回語(yǔ)句應(yīng)該是一個(gè)錯(cuò)誤 qDebug() init_group 函數(shù)執(zhí)行路徑錯(cuò)誤; return -1; // 或者拋出異常取決于您希望如何處理這種情況 }1、QUdpSocket::ShareAddress這個(gè)選項(xiàng)告訴操作系統(tǒng)允許多個(gè)QUdpSocket對(duì)象綁定到同一個(gè)地址和端口上。在默認(rèn)情況下操作系統(tǒng)可能會(huì)阻止多個(gè) socket 綁定到相同的地址和端口但是如果設(shè)置了ShareAddress選項(xiàng)Qt 會(huì)嘗試在可能的情況下共享這個(gè)地址和端口。在實(shí)際應(yīng)用中如果需要多個(gè)QUdpSocket對(duì)象同時(shí)監(jiān)聽(tīng)相同的地址和端口可以使用ShareAddress選項(xiàng)來(lái)避免綁定失敗的問(wèn)題。想象一下你和朋友們想在同一個(gè)電話號(hào)碼上收發(fā)短信。默認(rèn)情況下操作系統(tǒng)可能會(huì)阻止多個(gè)程序或者多個(gè)QUdpSocket對(duì)象同時(shí)使用同一個(gè)網(wǎng)絡(luò)地址IP 地址和端口號(hào)。但是如果你打開(kāi)了ShareAddress選項(xiàng)就像是你和朋友們一起共享一個(gè)電話號(hào)碼大家可以同時(shí)收發(fā)信息。這個(gè)選項(xiàng)讓多個(gè)QUdpSocket對(duì)象可以在同一個(gè)網(wǎng)絡(luò)地址和端口上工作而不會(huì)相互干擾或者造成綁定失敗的問(wèn)題。2、QUdpSocket::ReuseAddressHint這個(gè)選項(xiàng)告訴操作系統(tǒng)允許在 UDP Socket 關(guān)閉之后立即重新使用相同的地址和端口。如果沒(méi)有設(shè)置這個(gè)選項(xiàng)操作系統(tǒng)會(huì)在QUdpSocket關(guān)閉后一段時(shí)間內(nèi)保持端口的占用狀態(tài)這可能會(huì)導(dǎo)致稍后嘗試重新綁定失敗。設(shè)置ReuseAddressHint可以避免在關(guān)閉一個(gè)QUdpSocket后立即重新綁定時(shí)遇到Address already in use的錯(cuò)誤。想象一下你用一個(gè)電話號(hào)碼打電話然后掛了電話。在一段時(shí)間內(nèi)電話號(hào)碼可能會(huì)被暫時(shí)保留不允許其他人再用。這就好比默認(rèn)情況下當(dāng)一個(gè)QUdpSocket關(guān)閉后操作系統(tǒng)可能會(huì)暫時(shí)保留使用的網(wǎng)絡(luò)地址和端口號(hào)不讓其他程序立即使用。如果你設(shè)置了ReuseAddressHint就像是告訴操作系統(tǒng)“我關(guān)掉電話后如果其他人想用這個(gè)電話號(hào)碼可以立刻用不用等?！?這個(gè)選項(xiàng)允許在一個(gè)QUdpSocket關(guān)閉后立即重新使用相同的網(wǎng)絡(luò)地址和端口號(hào)而不會(huì)遇到“地址已經(jīng)被占用”的錯(cuò)誤?？偨Y(jié)使用后可以重復(fù)ip和端口7、發(fā)送消息socket-writeDatagram(str,targetAddress,targetPort);8、接收消息//接收消息 connect(udpSocket,QUdpSocket::readyRead,this,[](){ QByteArray datagram; datagram.resize(udpSocket-pendingDatagramSize()); udpSocket-readDatagram(datagram.data(), datagram.size()); ui-recvTextEdit-append(datagram); });9、退出組播int MainWindow::exit_group(QUdpSocket *socket ,QNetworkInterface currentInterface, QHostAddress targetAddress) { if(socket-leaveMulticastGroup(targetAddresscurrentInterface)){ socket-abort(); qDebug() 退出組播成功; return 1; }else{ qDebug() 退出組播失敗; return -1; } }四、多網(wǎng)卡場(chǎng)景下組播bind與setMulticastInterface的必要性在多網(wǎng)卡情況下只要bind綁定了IP地址和joinMulticastGroup加入了組播就用不上setMulticastInterface設(shè)置網(wǎng)卡函數(shù)那為什么有setMulticastInterface函數(shù)作用是什么呢場(chǎng)景1已綁定具體IP接口已確定QUdpSocket socket; QNetworkInterface eth0 QNetworkInterface::interfaceFromName(eth0); QHostAddress eth0IP eth0.addressEntries().first().ip(); // 綁定具體IP地址 socket.bind(eth0IP, 12345, QUdpSocket::ShareAddress); // 已指定接口 // 加入組播組 socket.joinMulticastGroup(QHostAddress(224.1.1.1)); // ? 不需要setMulticastInterface場(chǎng)景2綁定所有接口但需指定接收接口QUdpSocket socket; // 綁定所有接口 socket.bind(QHostAddress::Any, 12345, QUdpSocket::ShareAddress); // 加入組播組未指定接口 socket.joinMulticastGroup(QHostAddress(224.1.1.1)); // ? 系統(tǒng)可能隨機(jī)選擇接口 // ? 需要使用setMulticastInterface指定接口 socket.setMulticastInterface(eth0);五、得到當(dāng)前真實(shí)網(wǎng)卡IPQString Widget::get_current_IP() { QListQNetworkInterface interfaceList QNetworkInterface::allInterfaces(); foreach (QNetworkInterface nif, interfaceList) { // 檢查網(wǎng)卡是否有效并已經(jīng)啟用 if (nif.isValid() nif.flags().testFlag(QNetworkInterface::IsUp) nif.type() QNetworkInterface::Ethernet (nif.humanReadableName().contains(Realtek, Qt::CaseInsensitive) || nif.humanReadableName().contains(以太網(wǎng), Qt::CaseInsensitive))) { // 找出對(duì)應(yīng)的IP QListQNetworkAddressEntry entries nif.addressEntries(); foreach (QNetworkAddressEntry entry, entries) { if (entry.ip().protocol() QAbstractSocket::IPv4Protocol) { ui-nif_config-setText(entry.ip().toString()); return entry.ip().toString(); qDebug() Interface: nif.name() IP: entry.ip().toString(); } } } } return ; }ai方案QString Widget::get_current_IP() { QStringList validIps; const QListQNetworkInterface interfaces QNetworkInterface::allInterfaces(); for (const QNetworkInterface interface : interfaces) { // 1. 跳過(guò)非物理網(wǎng)卡或非以太網(wǎng)類型的接口 if (!interface.isValid() || interface.type() ! QNetworkInterface::Ethernet || interface.hardwareAddress().isEmpty()) { // 硬件地址為空可能是虛擬網(wǎng)卡 continue; } // 2. 確認(rèn)網(wǎng)卡狀態(tài)已啟用、未回環(huán)、已連接 const bool isUp interface.flags().testFlag(QNetworkInterface::IsUp); const bool isRunning interface.flags().testFlag(QNetworkInterface::IsRunning); // 關(guān)鍵檢查物理連接狀態(tài) const bool isLoopback interface.flags().testFlag(QNetworkInterface::IsLoopBack); if (!isUp || !isRunning || isLoopback) { continue; } // 3. 只處理有線以太網(wǎng)接口 if (interface.type() ! QNetworkInterface::Ethernet) { continue; } // 4. 獲取所有IPv4地址已確認(rèn)是有線連接 for (const QNetworkAddressEntry entry : interface.addressEntries()) { const QHostAddress ip entry.ip(); // 5. 只處理IPv4地址并排除特殊地址 if (ip.protocol() ! QAbstractSocket::IPv4Protocol || ip.isLoopback() || ip.isMulticast() || ip.isLinkLocal()) { // 169.254.x.x continue; } const QString ipStr ip.toString(); validIps ipStr; qDebug() Found wired IP: ipStr on interface: interface.name() ( interface.hardwareAddress() ); } } // 6. 返回處理邏輯 if (!validIps.isEmpty()) { // 優(yōu)選公共IP地址 for (const QString ipStr : validIps) { QHostAddress addr(ipStr); if (addr.isGlobal()) { return ipStr; // 優(yōu)先返回公共IP } } // 沒(méi)有公共IP時(shí)返回第一個(gè)找到的IP return validIps.first(); } return QString(); // 返回空字符串表示未找到 }六、動(dòng)態(tài)IP 定時(shí)器刷新1、創(chuàng)建定時(shí)器timer new MyTimer; timer-start(FLASH_NETWORK_TIME); connect(timer,MyTimer::timeout,this,MainWindow::slt_scanNetwork);2、實(shí)現(xiàn)函數(shù) slt_scanNetworkvoid MainWindow::slt_scanNetwork() { //----------有網(wǎng)口熱插拔---------- quint8 validInterFaceCount 0;//有效網(wǎng)卡數(shù)量 // 獲取所有網(wǎng)絡(luò)接口 QListQNetworkInterface interfaces QNetworkInterface::allInterfaces(); foreach (QNetworkInterface nif, interfaces) { // 檢查網(wǎng)卡是否有效并已經(jīng)啟用 if (nif.isValid() nif.flags().testFlag(QNetworkInterface::IsUp)) { validInterFaceCount; } } if(validInterFaceCount netlist.size()){ return; }else{ QString old ui-netInfCombo-currentText(); emit sgl_flashNet(netlist,ui-netInfCombo); if(old.isEmpty()){ return; } if(ui-netInfCombo-findText(old) ! -1){ ui-netInfCombo-setCurrentText(old); }else{ emit sgl_exitUniCast(); } // 有本地IP就加載到本地IP上 if(ui-netInfCombo-findText(get_current_IP()) ! -1){ ui-netInfCombo-setCurrentText(get_current_IP()); } } }3、實(shí)現(xiàn)刷新網(wǎng)口函數(shù) init_or_flash_NetInterfaceInfoToComboxconnect(this,Widget::sgl_flashNet,this,[](QListQNetworkInterface list, QComboBox *combox){ myUdpTool-init_or_flash_NetInterfaceInfoToCombox(list,combox); });void MyUdpTools::init_or_flash_NetInterfaceInfoToCombox(QListQNetworkInterface list, QComboBox *combox) { if(!list.isEmpty()){ list.clear(); } if(combox-count() ! 0){ combox-clear(); } QListQNetworkInterface interfaceList QNetworkInterface::allInterfaces(); foreach (QNetworkInterface nif, interfaceList) { // 檢查網(wǎng)卡是否有效并已經(jīng)啟用 if (nif.isValid() nif.flags().testFlag(QNetworkInterface::IsUp)) { // 將已經(jīng)啟用的網(wǎng)卡名稱添加到列表中 list.append(nif); QListQNetworkAddressEntry entries nif.addressEntries(); foreach (QNetworkAddressEntry entry, entries) { if (entry.ip().protocol() QAbstractSocket::IPv4Protocol) { combox-addItem(entry.ip().toString()); } } } } }七、自定義UDP工具類MyUdpTools.h#ifndef MYUDPTOOLS_H #define MYUDPTOOLS_H #include QObject #include QThread #include QComboBox #include QUdpSocket #include QMessageBox #include QApplication #include QNetworkDatagram #include QNetworkInterface class MyUdpTools : public QObject { Q_OBJECT public: explicit MyUdpTools(QObject *parent nullptr); ~MyUdpTools(); // 單播相關(guān)方法 int setupUnicast(QString currentNetInterfacrAddress, quint16 port 0); void sendUnicastData(QString targetAddress,quint16 port,const QByteArray data); int exitUnicast(); // 組播相關(guān)方法 int setupMulticast(QNetworkInterface netInterface,QString currentNetInterfacrAddress,QString groupAddress, quint16 port 0); void sendMulticastData(QString targetAddress,quint16 port,const QByteArray data); int exitMulticast(); // 廣播相關(guān)方法 int setupBroadcast(QString currentNetInterfacrAddress,QString targetAddress,quint16 port 0); void sendBroadcastData(QString targetAddress,quint16 port,const QByteArray data); int exitBroadcast(); //添加或刷新combox的網(wǎng)卡信息 void init_or_flash_NetInterfaceInfoToCombox(QListQNetworkInterface list,QComboBox *combox); signals: void sig_RecvData(QByteArray data); private slots: void processPendingDatagrams();//接收數(shù)據(jù)槽函數(shù) void handleSocketError(QAbstractSocket::SocketError socketError);//Udp錯(cuò)誤日志 private: QThread *thread; QHostAddress localAddress;//本機(jī)當(dāng)前網(wǎng)卡ip QUdpSocket *unicastSocket;//單播 quint16 unicastPort_Local;//單播本地端口 quint16 unicastPort_Target;//單播目標(biāo)端口 QHostAddress targetAddress_Unicast;//單播目標(biāo)地址 QUdpSocket *multicastSocket;//組播 QHostAddress multicastGroupAddress;//組播地址 quint16 multicastPort_Local;//組播本地端口 quint16 multicastPort_Target;//組播目標(biāo)端口 QUdpSocket *broadcastSocket;//廣播 QHostAddress broadcastGroupAddress;//廣播地址 quint16 broadcastPort_Local;//廣播本地端口 quint16 broadcastPort_Target;//廣播目標(biāo)端口 }; #endif // MYUDPTOOLS_HMyUdpTools.cpp#include myudptools.h MyUdpTools::MyUdpTools(QObject *parent) : QObject(parent),unicastSocket(nullptr),multicastSocket(nullptr),broadcastSocket(nullptr) { qInfo() 主線程: QThread::currentThreadId(); qRegisterMetaTypeQNetworkInterface(QNetworkInterface); thread new QThread(); moveToThread(thread); //應(yīng)用程序關(guān)閉后觸發(fā) connect(qApp,QApplication::aboutToQuit,thread, QThread::quit); //線程退出后觸發(fā) connect(thread, QThread::finished, thread, QThread::deleteLater); connect(thread,QThread::finished,this,MyUdpTools::deleteLater); // 在子線程中直接調(diào)用函數(shù) // QMetaObject::invokeMethod(this, init_or_flash_NetInterfaceInfoToCombox, Qt::QueuedConnection); //啟動(dòng)線程 thread-start(); } MyUdpTools::~MyUdpTools() { if(unicastSocket){ delete unicastSocket; } if(multicastSocket){ delete multicastSocket; } if(broadcastSocket){ delete broadcastSocket; } } //單播相關(guān)方法實(shí)現(xiàn) int MyUdpTools::setupUnicast(QString currentNetInterfacrAddress, quint16 port) { if (!unicastSocket) { connect(unicastSocket, QUdpSocket::readyRead, this, MyUdpTools::processPendingDatagrams); unicastSocket new QUdpSocket(this);//將父對(duì)象設(shè)置為當(dāng)前對(duì)象 connect(unicastSocket, SIGNAL(error(QAbstractSocket::SocketError)),this, SLOT(handleSocketError(QAbstractSocket::SocketError))); qInfo() 創(chuàng)建單播socket; } localAddress QHostAddress(currentNetInterfacrAddress); unicastPort_Local port; if(port 0){ if (!unicastSocket-bind(localAddress,QUdpSocket::ReuseAddressHint|QUdpSocket::ShareAddress)) { qCritical() 單播綁定失敗: unicastSocket-errorString(); return -1; } }else{ if (!unicastSocket-bind(localAddress, unicastPort_Local,QUdpSocket::ReuseAddressHint|QUdpSocket::ShareAddress)) { qCritical() 單播綁定失敗: unicastSocket-errorString(); return -1; } } qInfo() 單播連接成功; return 1; } void MyUdpTools::sendUnicastData(QString targetAddress, quint16 port, const QByteArray data) { if(unicastSocket){ targetAddress_Unicast QHostAddress(targetAddress); unicastPort_Target port; if(unicastSocket-writeDatagram(data,targetAddress_Unicast,unicastPort_Target) -1){ qCritical() 發(fā)送單播數(shù)據(jù)失敗: unicastSocket-errorString(); } } } int MyUdpTools::exitUnicast() { if (unicastSocket) { unicastSocket-close(); unicastSocket nullptr; qCritical() 退出成功; return 1; }else{ qCritical() 已退出單播無(wú)需再退出; return -1; } } //組播相關(guān)方法實(shí)現(xiàn) int MyUdpTools::setupMulticast(QNetworkInterface netInterface,QString currentNetInterfacrAddress, QString groupAddress, quint16 port) { if(!multicastSocket){ multicastSocket new QUdpSocket(this); connect(multicastSocket, QUdpSocket::readyRead, this, MyUdpTools::processPendingDatagrams); connect(multicastSocket, SIGNAL(error(QAbstractSocket::SocketError)),this, SLOT(handleSocketError(QAbstractSocket::SocketError))); qInfo() 創(chuàng)建組播socket; } localAddress QHostAddress(currentNetInterfacrAddress); multicastGroupAddress QHostAddress(groupAddress); multicastPort_Local port; if(!multicastGroupAddress.isMulticast()){ qWarning() 不是組播地址; return -1; } if(port 0){ if(!multicastSocket-bind(localAddress,QUdpSocket::ReuseAddressHint|QUdpSocket::ShareAddress)){ qCritical() 組播綁定失敗: multicastSocket-errorString(); return -1; } }else{ if(!multicastSocket-bind(localAddress,multicastPort_Local,QUdpSocket::ReuseAddressHint|QUdpSocket::ShareAddress)){ qCritical() 組播綁定失敗: multicastSocket-errorString(); return -1; } } multicastSocket-setMulticastInterface(netInterface); if(!multicastSocket-joinMulticastGroup(multicastGroupAddress,netInterface)){ qCritical() 加入組播失敗: multicastSocket-errorString(); return -1; } qInfo() 組播連接成功; return 1; } void MyUdpTools::sendMulticastData(QString targetAddress, quint16 port, const QByteArray data) { if(multicastSocket){ multicastGroupAddress QHostAddress(targetAddress); multicastPort_Target port; if(multicastSocket-writeDatagram(data,multicastGroupAddress,multicastPort_Target) -1){ qCritical() 發(fā)送組播數(shù)據(jù)失敗: multicastSocket-errorString(); } } } int MyUdpTools::exitMulticast() { if (multicastSocket) { multicastSocket-leaveMulticastGroup(multicastGroupAddress); // 確保在退出組播后關(guān)閉套接字 multicastSocket-close(); // 刪除套接字指針 multicastSocket nullptr; qInfo() 退出組播成功; return 1; }else{ qCritical() 已退出組播,無(wú)需再退出; return -1; } } //廣播相關(guān)方法實(shí)現(xiàn) int MyUdpTools::setupBroadcast(QString currentNetInterfaceAddress,QString targetAddress, quint16 port) { if (!broadcastSocket) { broadcastSocket new QUdpSocket(this);//將父對(duì)象設(shè)置為當(dāng)前對(duì)象 connect(broadcastSocket, QUdpSocket::readyRead, this, MyUdpTools::processPendingDatagrams); connect(broadcastSocket, SIGNAL(error(QAbstractSocket::SocketError)),this, SLOT(handleSocketError(QAbstractSocket::SocketError))); qInfo() 創(chuàng)建廣播socket; } localAddress QHostAddress(currentNetInterfaceAddress); broadcastPort_Local port; broadcastGroupAddress QHostAddress(targetAddress); if(!broadcastGroupAddress.isBroadcast()){ qCritical() 不是廣播地址; return -1; } if(port 0){ if (!broadcastSocket-bind(localAddress,QUdpSocket::ReuseAddressHint|QUdpSocket::ShareAddress)) { qCritical() 廣播綁定失敗: broadcastSocket-errorString(); return -1; } }else{ if (!broadcastSocket-bind(localAddress, broadcastPort_Local,QUdpSocket::ReuseAddressHint|QUdpSocket::ShareAddress)) { qCritical() 廣播綁定失敗: broadcastSocket-errorString(); return -1; } } qInfo() 連接成功; return 1; } void MyUdpTools::sendBroadcastData(QString targetAddress, quint16 port, const QByteArray data) { if(broadcastSocket){ broadcastGroupAddress QHostAddress(targetAddress); broadcastPort_Target port; if(broadcastSocket-writeDatagram(data,broadcastGroupAddress,broadcastPort_Target) -1){ qCritical() 發(fā)送廣播數(shù)據(jù)失敗: broadcastSocket-errorString(); } } } int MyUdpTools::exitBroadcast() { if (broadcastSocket) { broadcastSocket-close(); broadcastSocket nullptr; qInfo() 退出成功; return 1; }else{ qDebug() 已退出廣播,無(wú)需再退出; return -1; } } //添加或刷新combox的網(wǎng)卡信息函數(shù)實(shí)現(xiàn) void MyUdpTools::init_or_flash_NetInterfaceInfoToCombox(QListQNetworkInterface list, QComboBox *combox) { list.clear(); combox-clear(); QListQNetworkInterface interfaceList QNetworkInterface::allInterfaces(); foreach (QNetworkInterface nif, interfaceList) { // 檢查網(wǎng)卡是否有效并已經(jīng)啟用 if (nif.isValid() nif.flags().testFlag(QNetworkInterface::IsUp)) { // 將已經(jīng)啟用的網(wǎng)卡名稱添加到列表中 list.append(nif); QListQNetworkAddressEntry entries nif.addressEntries(); foreach (QNetworkAddressEntry entry, entries) { if (entry.ip().protocol() QAbstractSocket::IPv4Protocol) { combox-addItem(entry.ip().toString()); } } } } } //接收數(shù)據(jù)槽函數(shù)實(shí)現(xiàn) void MyUdpTools::processPendingDatagrams() { QUdpSocket *socket qobject_castQUdpSocket *(sender());//sender()發(fā)送信號(hào)的對(duì)象的指針 if (!socket) return; while (socket-hasPendingDatagrams()) { #if 1 QByteArray datagram; datagram.resize(socket-pendingDatagramSize()); socket-readDatagram(datagram.data(), datagram.size()); qDebug() Received Data: datagram; emit sig_RecvData(datagram); #else QNetworkDatagram datagram socket-receiveDatagram(); QByteArray data datagram.data(); qDebug() Received Data: datagram; emit sig_RecvData(data); #endif } } //Udp錯(cuò)誤日志信息 void MyUdpTools::handleSocketError(QAbstractSocket::SocketError socketError) { QUdpSocket *socket qobject_castQUdpSocket *(sender()); if (!socket) return; switch (socketError) { case QAbstractSocket::HostNotFoundError: qCritical() Host not found error: socket-errorString(); break; case QAbstractSocket::ConnectionRefusedError: qCritical() Connection refused error: socket-errorString(); break; case QAbstractSocket::DatagramTooLargeError: qCritical() Datagram too large error: socket-errorString(); break; default: qCritical() Socket error: socket-errorString(); break; } }注意為什么new QThread();不能指定父對(duì)象為this如果指定父對(duì)象為this的話QThread的生命周期就由其父對(duì)象MyUdpTools管理不是由QThread直接管理這不是推薦的做法。不同線程之間的通信要用信號(hào)與槽進(jìn)行通信。在子線程中不能調(diào)用函數(shù)會(huì)影響線程安全可以在主線程中使用函數(shù)QMetaObject::invokeMethod 使得 子線程能直接調(diào)用函數(shù)。 Qt實(shí)現(xiàn)UDP單播、組播和廣播功能
一、UDP單播、廣播和組播的說(shuō)明UDP是不可靠、無(wú)連接的所以劃分為發(fā)送方和接收方更好理解1、單播UDP是無(wú)連接的進(jìn)行單播通信時(shí)必須要綁定接收方端口發(fā)送方直接通過(guò)接收方的ip和綁定的端口進(jìn)行通信。發(fā)送方可以綁定端口也可以不用綁定端口不綁定端口的話系統(tǒng)會(huì)隨機(jī)分配端口。對(duì)于多網(wǎng)卡來(lái)說(shuō)需要指定網(wǎng)卡綁定一個(gè)網(wǎng)卡的ip。如果不進(jìn)行顯式的綁定操作QUdpSocket對(duì)象將會(huì)使用默認(rèn)的綁定方式自動(dòng)選擇一個(gè)可用的 ip 地址進(jìn)行綁定。2、廣播對(duì)于只有1個(gè)網(wǎng)卡的主機(jī)來(lái)說(shuō)可以不用顯示綁定ip發(fā)送方直接發(fā)送廣播就行接收方綁定廣播端口就行這樣才能看到收到的消息。對(duì)于多網(wǎng)卡來(lái)說(shuō)要指定唯一的網(wǎng)卡ip并且在廣播前要綁定廣播端口。ip可以不用綁定這樣系統(tǒng)會(huì)隨機(jī)分配一個(gè)網(wǎng)卡ip。3、組播對(duì)于只有1個(gè)網(wǎng)卡的主機(jī)來(lái)說(shuō)可以不用綁定ip直接綁定端口后加入組播就行。系統(tǒng)分配任意一個(gè)ip 相當(dāng)于QHostAddress::AnyIPv4。對(duì)于多網(wǎng)卡來(lái)說(shuō)要指定唯一的網(wǎng)卡并且在加入組播前要綁定組播端口ip可以不用綁定系統(tǒng)分配任意一個(gè)ip。注意指定網(wǎng)卡不等于指定ip1、使用setMulticastInterface方法可以指定一個(gè)明確的網(wǎng)卡但并不意味著只有一個(gè) IP 地址。一個(gè)網(wǎng)卡可以綁定多個(gè) IP 地址例如在同一臺(tái)主機(jī)上同時(shí)存在有線網(wǎng)卡和無(wú)線網(wǎng)卡它們可能都連接到同一局域網(wǎng)并分別配置了不同的 IP 地址。此時(shí)通過(guò)setMulticastInterface方法指定了一個(gè)明確的網(wǎng)卡后并不確定使用哪個(gè) IP 地址來(lái)進(jìn)行組播通信。如果需要確保使用特定的 IP 地址進(jìn)行組播通信則需要使用bind方法來(lái)將QUdpSocket對(duì)象綁定到具體的 IP 地址和端口上這樣每次進(jìn)行組播通信時(shí)都會(huì)使用該 IP 地址來(lái)發(fā)送和接收數(shù)據(jù)報(bào)文。2、使用QHostAddress::AnyIPv4參數(shù)可以將QUdpSocket對(duì)象綁定到本機(jī)的所有 IPv4 地址。這意味著該QUdpSocket對(duì)象可以接收通過(guò)本機(jī)的任意一個(gè) IPv4 地址發(fā)送到指定端口的數(shù)據(jù)包。然而需要注意的是綁定到多個(gè) IPv4 地址并不意味著可以同時(shí)從多個(gè)地址接收數(shù)據(jù)包。在任何給定的時(shí)刻QUdpSocket對(duì)象只能通過(guò)一個(gè) IP 地址接收數(shù)據(jù)包。當(dāng)有多個(gè) IPv4 地址可用時(shí)QUdpSocket對(duì)象會(huì)選擇其中一個(gè)地址來(lái)接收數(shù)據(jù)包。這個(gè)選擇通常由操作系統(tǒng)或網(wǎng)絡(luò)棧決定并且可能會(huì)受到各種因素的影響例如網(wǎng)絡(luò)接口的優(yōu)先級(jí)、路由表等。因此使用QHostAddress::AnyIPv4參數(shù)可以讓QUdpSocket對(duì)象綁定到本機(jī)的所有 IPv4 地址但實(shí)際上它只能通過(guò)其中一個(gè)地址接收數(shù)據(jù)包。具體使用哪個(gè)地址取決于操作系統(tǒng)和網(wǎng)絡(luò)環(huán)境。二、遇到的UDP通信的問(wèn)題參考查看所有端口netstat -ano查看某個(gè)端口netstat -ano | findstr 端口號(hào)查看TCP的socket信息netstat -an | find TCP查看UDP的socket信息netstat -an | find UDP關(guān)于QT UDP組播的幾個(gè)問(wèn)題https://blog.csdn.net/tom06/article/details/52163665?spm1001.2014.3001.5506UDP多播/組播通信同一局域網(wǎng)下的兩臺(tái)機(jī)器通信接收不到數(shù)據(jù)https://blog.csdn.net/qq_43290013/article/details/117288296?spm1001.2014.3001.5506QT讀取網(wǎng)卡列表多網(wǎng)卡綁定組播網(wǎng)卡https://blog.csdn.net/qq_30727593/article/details/127441711?spm1001.2014.3001.5506三、效果與代碼1、在.pro文件中添加如下內(nèi)容QT network2、在.h文件中添加串口所用的頭文件#include QUdpSocket #include QNetworkInterface3、添加一個(gè)QUdpSocket* socket的類成員并在.cpp中實(shí)例化對(duì)象socket new QUdpSocket;4、掃描可用網(wǎng)口QListQNetworkInterface interfaceList QNetworkInterface::allInterfaces(); foreach (QNetworkInterface nif, interfaceList) { // 檢查網(wǎng)卡是否有效并已經(jīng)啟用 if (nif.isValid() nif.flags().testFlag(QNetworkInterface::IsUp)) { // 將已經(jīng)啟用的網(wǎng)卡名稱添加到列表中 enabledInterfaceList.append(nif); QListQNetworkAddressEntry entries nif.addressEntries(); foreach (QNetworkAddressEntry entry, entries) { if (entry.ip().protocol() QAbstractSocket::IPv4Protocol) { if(entry.ip().toString() localIP){ index; }; } } } }5、對(duì)組播進(jìn)行設(shè)置可以忽略//組播的數(shù)據(jù)的生存期數(shù)據(jù)報(bào)沒(méi)跨1個(gè)路由就會(huì)減1.表示多播數(shù)據(jù)報(bào)只能在同一路由下的局域網(wǎng)內(nèi)傳播 socket-setSocketOption(QAbstractSocket::MulticastTtlOption,1); //1是允許loopback模式自發(fā)自收,0是阻止。 socket-setSocketOption(QAbstractSocket::MulticastLoopbackOption, true);6、初始化組播設(shè)置int MainWindow::init_group(QUdpSocket *socket, QNetworkInterface currentInterface, QHostAddress localAddress, QHostAddress targetAddress, int localPort) { if (targetAddress.isMulticast()) {//isMulticast()判斷是否是組播地址 if (localPort 0) {//判斷是否指定本地端口 //bind(localAddress, QUdpSocket::ShareAddress | QUdpSocket::ReuseAddressHint)可以換成bind(QHostAddress::AnyIPv4, QUdpSocket::ShareAddress | QUdpSocket::ReuseAddressHint) if (socket-bind(localAddress, QUdpSocket::ShareAddress | QUdpSocket::ReuseAddressHint)) { socket-setMulticastInterface(currentInterface); if (socket-joinMulticastGroup(targetAddress, currentInterface)) { qDebug() 未指定本地端口,加入組播成功; return 1; } else { qDebug() 未指定本地端口,加入組播失敗; return -1; } } else { qDebug() 未指定本地端口,綁定失敗; return -1; } } else { if (socket-bind(localAddress, localPort, QUdpSocket::ShareAddress | QUdpSocket::ReuseAddressHint)) { socket-setMulticastInterface(currentInterface); if (socket-joinMulticastGroup(targetAddress, currentInterface)) { qDebug() 指定本地端口,加入組播成功; return 1; } else { qDebug() 指定本地端口,加入組播失敗; return -1; } } else { qDebug() 指定本地端口,綁定失敗; return -1; } } } else { qDebug() 目標(biāo)地址不是組播地址; return -1; } // 如果執(zhí)行到這里說(shuō)明沒(méi)有通過(guò)任何返回語(yǔ)句應(yīng)該是一個(gè)錯(cuò)誤 qDebug() init_group 函數(shù)執(zhí)行路徑錯(cuò)誤; return -1; // 或者拋出異常取決于您希望如何處理這種情況 }1、QUdpSocket::ShareAddress這個(gè)選項(xiàng)告訴操作系統(tǒng)允許多個(gè)QUdpSocket對(duì)象綁定到同一個(gè)地址和端口上。在默認(rèn)情況下操作系統(tǒng)可能會(huì)阻止多個(gè) socket 綁定到相同的地址和端口但是如果設(shè)置了ShareAddress選項(xiàng)Qt 會(huì)嘗試在可能的情況下共享這個(gè)地址和端口。在實(shí)際應(yīng)用中如果需要多個(gè)QUdpSocket對(duì)象同時(shí)監(jiān)聽(tīng)相同的地址和端口可以使用ShareAddress選項(xiàng)來(lái)避免綁定失敗的問(wèn)題。想象一下你和朋友們想在同一個(gè)電話號(hào)碼上收發(fā)短信。默認(rèn)情況下操作系統(tǒng)可能會(huì)阻止多個(gè)程序或者多個(gè)QUdpSocket對(duì)象同時(shí)使用同一個(gè)網(wǎng)絡(luò)地址IP 地址和端口號(hào)。但是如果你打開(kāi)了ShareAddress選項(xiàng)就像是你和朋友們一起共享一個(gè)電話號(hào)碼大家可以同時(shí)收發(fā)信息。這個(gè)選項(xiàng)讓多個(gè)QUdpSocket對(duì)象可以在同一個(gè)網(wǎng)絡(luò)地址和端口上工作而不會(huì)相互干擾或者造成綁定失敗的問(wèn)題。2、QUdpSocket::ReuseAddressHint這個(gè)選項(xiàng)告訴操作系統(tǒng)允許在 UDP Socket 關(guān)閉之后立即重新使用相同的地址和端口。如果沒(méi)有設(shè)置這個(gè)選項(xiàng)操作系統(tǒng)會(huì)在QUdpSocket關(guān)閉后一段時(shí)間內(nèi)保持端口的占用狀態(tài)這可能會(huì)導(dǎo)致稍后嘗試重新綁定失敗。設(shè)置ReuseAddressHint可以避免在關(guān)閉一個(gè)QUdpSocket后立即重新綁定時(shí)遇到Address already in use的錯(cuò)誤。想象一下你用一個(gè)電話號(hào)碼打電話然后掛了電話。在一段時(shí)間內(nèi)電話號(hào)碼可能會(huì)被暫時(shí)保留不允許其他人再用。這就好比默認(rèn)情況下當(dāng)一個(gè)QUdpSocket關(guān)閉后操作系統(tǒng)可能會(huì)暫時(shí)保留使用的網(wǎng)絡(luò)地址和端口號(hào)不讓其他程序立即使用。如果你設(shè)置了ReuseAddressHint就像是告訴操作系統(tǒng)“我關(guān)掉電話后如果其他人想用這個(gè)電話號(hào)碼可以立刻用不用等?！?這個(gè)選項(xiàng)允許在一個(gè)QUdpSocket關(guān)閉后立即重新使用相同的網(wǎng)絡(luò)地址和端口號(hào)而不會(huì)遇到“地址已經(jīng)被占用”的錯(cuò)誤?？偨Y(jié)使用后可以重復(fù)ip和端口7、發(fā)送消息socket-writeDatagram(str,targetAddress,targetPort);8、接收消息//接收消息 connect(udpSocket,QUdpSocket::readyRead,this,[](){ QByteArray datagram; datagram.resize(udpSocket-pendingDatagramSize()); udpSocket-readDatagram(datagram.data(), datagram.size()); ui-recvTextEdit-append(datagram); });9、退出組播int MainWindow::exit_group(QUdpSocket *socket ,QNetworkInterface currentInterface, QHostAddress targetAddress) { if(socket-leaveMulticastGroup(targetAddresscurrentInterface)){ socket-abort(); qDebug() 退出組播成功; return 1; }else{ qDebug() 退出組播失敗; return -1; } }四、多網(wǎng)卡場(chǎng)景下組播bind與setMulticastInterface的必要性在多網(wǎng)卡情況下只要bind綁定了IP地址和joinMulticastGroup加入了組播就用不上setMulticastInterface設(shè)置網(wǎng)卡函數(shù)那為什么有setMulticastInterface函數(shù)作用是什么呢場(chǎng)景1已綁定具體IP接口已確定QUdpSocket socket; QNetworkInterface eth0 QNetworkInterface::interfaceFromName(eth0); QHostAddress eth0IP eth0.addressEntries().first().ip(); // 綁定具體IP地址 socket.bind(eth0IP, 12345, QUdpSocket::ShareAddress); // 已指定接口 // 加入組播組 socket.joinMulticastGroup(QHostAddress(224.1.1.1)); // ? 不需要setMulticastInterface場(chǎng)景2綁定所有接口但需指定接收接口QUdpSocket socket; // 綁定所有接口 socket.bind(QHostAddress::Any, 12345, QUdpSocket::ShareAddress); // 加入組播組未指定接口 socket.joinMulticastGroup(QHostAddress(224.1.1.1)); // ? 系統(tǒng)可能隨機(jī)選擇接口 // ? 需要使用setMulticastInterface指定接口 socket.setMulticastInterface(eth0);五、得到當(dāng)前真實(shí)網(wǎng)卡IPQString Widget::get_current_IP() { QListQNetworkInterface interfaceList QNetworkInterface::allInterfaces(); foreach (QNetworkInterface nif, interfaceList) { // 檢查網(wǎng)卡是否有效并已經(jīng)啟用 if (nif.isValid() nif.flags().testFlag(QNetworkInterface::IsUp) nif.type() QNetworkInterface::Ethernet (nif.humanReadableName().contains(Realtek, Qt::CaseInsensitive) || nif.humanReadableName().contains(以太網(wǎng), Qt::CaseInsensitive))) { // 找出對(duì)應(yīng)的IP QListQNetworkAddressEntry entries nif.addressEntries(); foreach (QNetworkAddressEntry entry, entries) { if (entry.ip().protocol() QAbstractSocket::IPv4Protocol) { ui-nif_config-setText(entry.ip().toString()); return entry.ip().toString(); qDebug() Interface: nif.name() IP: entry.ip().toString(); } } } } return ; }ai方案QString Widget::get_current_IP() { QStringList validIps; const QListQNetworkInterface interfaces QNetworkInterface::allInterfaces(); for (const QNetworkInterface interface : interfaces) { // 1. 跳過(guò)非物理網(wǎng)卡或非以太網(wǎng)類型的接口 if (!interface.isValid() || interface.type() ! QNetworkInterface::Ethernet || interface.hardwareAddress().isEmpty()) { // 硬件地址為空可能是虛擬網(wǎng)卡 continue; } // 2. 確認(rèn)網(wǎng)卡狀態(tài)已啟用、未回環(huán)、已連接 const bool isUp interface.flags().testFlag(QNetworkInterface::IsUp); const bool isRunning interface.flags().testFlag(QNetworkInterface::IsRunning); // 關(guān)鍵檢查物理連接狀態(tài) const bool isLoopback interface.flags().testFlag(QNetworkInterface::IsLoopBack); if (!isUp || !isRunning || isLoopback) { continue; } // 3. 只處理有線以太網(wǎng)接口 if (interface.type() ! QNetworkInterface::Ethernet) { continue; } // 4. 獲取所有IPv4地址已確認(rèn)是有線連接 for (const QNetworkAddressEntry entry : interface.addressEntries()) { const QHostAddress ip entry.ip(); // 5. 只處理IPv4地址并排除特殊地址 if (ip.protocol() ! QAbstractSocket::IPv4Protocol || ip.isLoopback() || ip.isMulticast() || ip.isLinkLocal()) { // 169.254.x.x continue; } const QString ipStr ip.toString(); validIps ipStr; qDebug() Found wired IP: ipStr on interface: interface.name() ( interface.hardwareAddress() ); } } // 6. 返回處理邏輯 if (!validIps.isEmpty()) { // 優(yōu)選公共IP地址 for (const QString ipStr : validIps) { QHostAddress addr(ipStr); if (addr.isGlobal()) { return ipStr; // 優(yōu)先返回公共IP } } // 沒(méi)有公共IP時(shí)返回第一個(gè)找到的IP return validIps.first(); } return QString(); // 返回空字符串表示未找到 }六、動(dòng)態(tài)IP 定時(shí)器刷新1、創(chuàng)建定時(shí)器timer new MyTimer; timer-start(FLASH_NETWORK_TIME); connect(timer,MyTimer::timeout,this,MainWindow::slt_scanNetwork);2、實(shí)現(xiàn)函數(shù) slt_scanNetworkvoid MainWindow::slt_scanNetwork() { //----------有網(wǎng)口熱插拔---------- quint8 validInterFaceCount 0;//有效網(wǎng)卡數(shù)量 // 獲取所有網(wǎng)絡(luò)接口 QListQNetworkInterface interfaces QNetworkInterface::allInterfaces(); foreach (QNetworkInterface nif, interfaces) { // 檢查網(wǎng)卡是否有效并已經(jīng)啟用 if (nif.isValid() nif.flags().testFlag(QNetworkInterface::IsUp)) { validInterFaceCount; } } if(validInterFaceCount netlist.size()){ return; }else{ QString old ui-netInfCombo-currentText(); emit sgl_flashNet(netlist,ui-netInfCombo); if(old.isEmpty()){ return; } if(ui-netInfCombo-findText(old) ! -1){ ui-netInfCombo-setCurrentText(old); }else{ emit sgl_exitUniCast(); } // 有本地IP就加載到本地IP上 if(ui-netInfCombo-findText(get_current_IP()) ! -1){ ui-netInfCombo-setCurrentText(get_current_IP()); } } }3、實(shí)現(xiàn)刷新網(wǎng)口函數(shù) init_or_flash_NetInterfaceInfoToComboxconnect(this,Widget::sgl_flashNet,this,[](QListQNetworkInterface list, QComboBox *combox){ myUdpTool-init_or_flash_NetInterfaceInfoToCombox(list,combox); });void MyUdpTools::init_or_flash_NetInterfaceInfoToCombox(QListQNetworkInterface list, QComboBox *combox) { if(!list.isEmpty()){ list.clear(); } if(combox-count() ! 0){ combox-clear(); } QListQNetworkInterface interfaceList QNetworkInterface::allInterfaces(); foreach (QNetworkInterface nif, interfaceList) { // 檢查網(wǎng)卡是否有效并已經(jīng)啟用 if (nif.isValid() nif.flags().testFlag(QNetworkInterface::IsUp)) { // 將已經(jīng)啟用的網(wǎng)卡名稱添加到列表中 list.append(nif); QListQNetworkAddressEntry entries nif.addressEntries(); foreach (QNetworkAddressEntry entry, entries) { if (entry.ip().protocol() QAbstractSocket::IPv4Protocol) { combox-addItem(entry.ip().toString()); } } } } }七、自定義UDP工具類MyUdpTools.h#ifndef MYUDPTOOLS_H #define MYUDPTOOLS_H #include QObject #include QThread #include QComboBox #include QUdpSocket #include QMessageBox #include QApplication #include QNetworkDatagram #include QNetworkInterface class MyUdpTools : public QObject { Q_OBJECT public: explicit MyUdpTools(QObject *parent nullptr); ~MyUdpTools(); // 單播相關(guān)方法 int setupUnicast(QString currentNetInterfacrAddress, quint16 port 0); void sendUnicastData(QString targetAddress,quint16 port,const QByteArray data); int exitUnicast(); // 組播相關(guān)方法 int setupMulticast(QNetworkInterface netInterface,QString currentNetInterfacrAddress,QString groupAddress, quint16 port 0); void sendMulticastData(QString targetAddress,quint16 port,const QByteArray data); int exitMulticast(); // 廣播相關(guān)方法 int setupBroadcast(QString currentNetInterfacrAddress,QString targetAddress,quint16 port 0); void sendBroadcastData(QString targetAddress,quint16 port,const QByteArray data); int exitBroadcast(); //添加或刷新combox的網(wǎng)卡信息 void init_or_flash_NetInterfaceInfoToCombox(QListQNetworkInterface list,QComboBox *combox); signals: void sig_RecvData(QByteArray data); private slots: void processPendingDatagrams();//接收數(shù)據(jù)槽函數(shù) void handleSocketError(QAbstractSocket::SocketError socketError);//Udp錯(cuò)誤日志 private: QThread *thread; QHostAddress localAddress;//本機(jī)當(dāng)前網(wǎng)卡ip QUdpSocket *unicastSocket;//單播 quint16 unicastPort_Local;//單播本地端口 quint16 unicastPort_Target;//單播目標(biāo)端口 QHostAddress targetAddress_Unicast;//單播目標(biāo)地址 QUdpSocket *multicastSocket;//組播 QHostAddress multicastGroupAddress;//組播地址 quint16 multicastPort_Local;//組播本地端口 quint16 multicastPort_Target;//組播目標(biāo)端口 QUdpSocket *broadcastSocket;//廣播 QHostAddress broadcastGroupAddress;//廣播地址 quint16 broadcastPort_Local;//廣播本地端口 quint16 broadcastPort_Target;//廣播目標(biāo)端口 }; #endif // MYUDPTOOLS_HMyUdpTools.cpp#include myudptools.h MyUdpTools::MyUdpTools(QObject *parent) : QObject(parent),unicastSocket(nullptr),multicastSocket(nullptr),broadcastSocket(nullptr) { qInfo() 主線程: QThread::currentThreadId(); qRegisterMetaTypeQNetworkInterface(QNetworkInterface); thread new QThread(); moveToThread(thread); //應(yīng)用程序關(guān)閉后觸發(fā) connect(qApp,QApplication::aboutToQuit,thread, QThread::quit); //線程退出后觸發(fā) connect(thread, QThread::finished, thread, QThread::deleteLater); connect(thread,QThread::finished,this,MyUdpTools::deleteLater); // 在子線程中直接調(diào)用函數(shù) // QMetaObject::invokeMethod(this, init_or_flash_NetInterfaceInfoToCombox, Qt::QueuedConnection); //啟動(dòng)線程 thread-start(); } MyUdpTools::~MyUdpTools() { if(unicastSocket){ delete unicastSocket; } if(multicastSocket){ delete multicastSocket; } if(broadcastSocket){ delete broadcastSocket; } } //單播相關(guān)方法實(shí)現(xiàn) int MyUdpTools::setupUnicast(QString currentNetInterfacrAddress, quint16 port) { if (!unicastSocket) { connect(unicastSocket, QUdpSocket::readyRead, this, MyUdpTools::processPendingDatagrams); unicastSocket new QUdpSocket(this);//將父對(duì)象設(shè)置為當(dāng)前對(duì)象 connect(unicastSocket, SIGNAL(error(QAbstractSocket::SocketError)),this, SLOT(handleSocketError(QAbstractSocket::SocketError))); qInfo() 創(chuàng)建單播socket; } localAddress QHostAddress(currentNetInterfacrAddress); unicastPort_Local port; if(port 0){ if (!unicastSocket-bind(localAddress,QUdpSocket::ReuseAddressHint|QUdpSocket::ShareAddress)) { qCritical() 單播綁定失敗: unicastSocket-errorString(); return -1; } }else{ if (!unicastSocket-bind(localAddress, unicastPort_Local,QUdpSocket::ReuseAddressHint|QUdpSocket::ShareAddress)) { qCritical() 單播綁定失敗: unicastSocket-errorString(); return -1; } } qInfo() 單播連接成功; return 1; } void MyUdpTools::sendUnicastData(QString targetAddress, quint16 port, const QByteArray data) { if(unicastSocket){ targetAddress_Unicast QHostAddress(targetAddress); unicastPort_Target port; if(unicastSocket-writeDatagram(data,targetAddress_Unicast,unicastPort_Target) -1){ qCritical() 發(fā)送單播數(shù)據(jù)失敗: unicastSocket-errorString(); } } } int MyUdpTools::exitUnicast() { if (unicastSocket) { unicastSocket-close(); unicastSocket nullptr; qCritical() 退出成功; return 1; }else{ qCritical() 已退出單播無(wú)需再退出; return -1; } } //組播相關(guān)方法實(shí)現(xiàn) int MyUdpTools::setupMulticast(QNetworkInterface netInterface,QString currentNetInterfacrAddress, QString groupAddress, quint16 port) { if(!multicastSocket){ multicastSocket new QUdpSocket(this); connect(multicastSocket, QUdpSocket::readyRead, this, MyUdpTools::processPendingDatagrams); connect(multicastSocket, SIGNAL(error(QAbstractSocket::SocketError)),this, SLOT(handleSocketError(QAbstractSocket::SocketError))); qInfo() 創(chuàng)建組播socket; } localAddress QHostAddress(currentNetInterfacrAddress); multicastGroupAddress QHostAddress(groupAddress); multicastPort_Local port; if(!multicastGroupAddress.isMulticast()){ qWarning() 不是組播地址; return -1; } if(port 0){ if(!multicastSocket-bind(localAddress,QUdpSocket::ReuseAddressHint|QUdpSocket::ShareAddress)){ qCritical() 組播綁定失敗: multicastSocket-errorString(); return -1; } }else{ if(!multicastSocket-bind(localAddress,multicastPort_Local,QUdpSocket::ReuseAddressHint|QUdpSocket::ShareAddress)){ qCritical() 組播綁定失敗: multicastSocket-errorString(); return -1; } } multicastSocket-setMulticastInterface(netInterface); if(!multicastSocket-joinMulticastGroup(multicastGroupAddress,netInterface)){ qCritical() 加入組播失敗: multicastSocket-errorString(); return -1; } qInfo() 組播連接成功; return 1; } void MyUdpTools::sendMulticastData(QString targetAddress, quint16 port, const QByteArray data) { if(multicastSocket){ multicastGroupAddress QHostAddress(targetAddress); multicastPort_Target port; if(multicastSocket-writeDatagram(data,multicastGroupAddress,multicastPort_Target) -1){ qCritical() 發(fā)送組播數(shù)據(jù)失敗: multicastSocket-errorString(); } } } int MyUdpTools::exitMulticast() { if (multicastSocket) { multicastSocket-leaveMulticastGroup(multicastGroupAddress); // 確保在退出組播后關(guān)閉套接字 multicastSocket-close(); // 刪除套接字指針 multicastSocket nullptr; qInfo() 退出組播成功; return 1; }else{ qCritical() 已退出組播,無(wú)需再退出; return -1; } } //廣播相關(guān)方法實(shí)現(xiàn) int MyUdpTools::setupBroadcast(QString currentNetInterfaceAddress,QString targetAddress, quint16 port) { if (!broadcastSocket) { broadcastSocket new QUdpSocket(this);//將父對(duì)象設(shè)置為當(dāng)前對(duì)象 connect(broadcastSocket, QUdpSocket::readyRead, this, MyUdpTools::processPendingDatagrams); connect(broadcastSocket, SIGNAL(error(QAbstractSocket::SocketError)),this, SLOT(handleSocketError(QAbstractSocket::SocketError))); qInfo() 創(chuàng)建廣播socket; } localAddress QHostAddress(currentNetInterfaceAddress); broadcastPort_Local port; broadcastGroupAddress QHostAddress(targetAddress); if(!broadcastGroupAddress.isBroadcast()){ qCritical() 不是廣播地址; return -1; } if(port 0){ if (!broadcastSocket-bind(localAddress,QUdpSocket::ReuseAddressHint|QUdpSocket::ShareAddress)) { qCritical() 廣播綁定失敗: broadcastSocket-errorString(); return -1; } }else{ if (!broadcastSocket-bind(localAddress, broadcastPort_Local,QUdpSocket::ReuseAddressHint|QUdpSocket::ShareAddress)) { qCritical() 廣播綁定失敗: broadcastSocket-errorString(); return -1; } } qInfo() 連接成功; return 1; } void MyUdpTools::sendBroadcastData(QString targetAddress, quint16 port, const QByteArray data) { if(broadcastSocket){ broadcastGroupAddress QHostAddress(targetAddress); broadcastPort_Target port; if(broadcastSocket-writeDatagram(data,broadcastGroupAddress,broadcastPort_Target) -1){ qCritical() 發(fā)送廣播數(shù)據(jù)失敗: broadcastSocket-errorString(); } } } int MyUdpTools::exitBroadcast() { if (broadcastSocket) { broadcastSocket-close(); broadcastSocket nullptr; qInfo() 退出成功; return 1; }else{ qDebug() 已退出廣播,無(wú)需再退出; return -1; } } //添加或刷新combox的網(wǎng)卡信息函數(shù)實(shí)現(xiàn) void MyUdpTools::init_or_flash_NetInterfaceInfoToCombox(QListQNetworkInterface list, QComboBox *combox) { list.clear(); combox-clear(); QListQNetworkInterface interfaceList QNetworkInterface::allInterfaces(); foreach (QNetworkInterface nif, interfaceList) { // 檢查網(wǎng)卡是否有效并已經(jīng)啟用 if (nif.isValid() nif.flags().testFlag(QNetworkInterface::IsUp)) { // 將已經(jīng)啟用的網(wǎng)卡名稱添加到列表中 list.append(nif); QListQNetworkAddressEntry entries nif.addressEntries(); foreach (QNetworkAddressEntry entry, entries) { if (entry.ip().protocol() QAbstractSocket::IPv4Protocol) { combox-addItem(entry.ip().toString()); } } } } } //接收數(shù)據(jù)槽函數(shù)實(shí)現(xiàn) void MyUdpTools::processPendingDatagrams() { QUdpSocket *socket qobject_castQUdpSocket *(sender());//sender()發(fā)送信號(hào)的對(duì)象的指針 if (!socket) return; while (socket-hasPendingDatagrams()) { #if 1 QByteArray datagram; datagram.resize(socket-pendingDatagramSize()); socket-readDatagram(datagram.data(), datagram.size()); qDebug() Received Data: datagram; emit sig_RecvData(datagram); #else QNetworkDatagram datagram socket-receiveDatagram(); QByteArray data datagram.data(); qDebug() Received Data: datagram; emit sig_RecvData(data); #endif } } //Udp錯(cuò)誤日志信息 void MyUdpTools::handleSocketError(QAbstractSocket::SocketError socketError) { QUdpSocket *socket qobject_castQUdpSocket *(sender()); if (!socket) return; switch (socketError) { case QAbstractSocket::HostNotFoundError: qCritical() Host not found error: socket-errorString(); break; case QAbstractSocket::ConnectionRefusedError: qCritical() Connection refused error: socket-errorString(); break; case QAbstractSocket::DatagramTooLargeError: qCritical() Datagram too large error: socket-errorString(); break; default: qCritical() Socket error: socket-errorString(); break; } }注意為什么new QThread();不能指定父對(duì)象為this如果指定父對(duì)象為this的話QThread的生命周期就由其父對(duì)象MyUdpTools管理不是由QThread直接管理這不是推薦的做法。不同線程之間的通信要用信號(hào)與槽進(jìn)行通信。在子線程中不能調(diào)用函數(shù)會(huì)影響線程安全可以在主線程中使用函數(shù)QMetaObject::invokeMethod 使得 子線程能直接調(diào)用函數(shù)。