QT获取电脑网卡IP等信息

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一、背景信息

电脑有一个或者多个网卡，如下图所示：

一个网卡又可以配有多个IP地址，包括 IPv4 和 IPv6 地址：

二、代码实现

以下代码实现了查找电脑所有网卡，并获取某个网卡的 IP 等信息：

int main() {
    // 获取所有网卡信息
    QComboBox *m_netCardComboBox;
    QList<QNetworkInterface> m_allInterfaces = QNetworkInterface::allInterfaces();
    for (int i = 0; i < m_allInterfaces.size(); ++i) {
        QNetworkInterface netInterface = m_allInterfaces.at(i);
        m_netCardComboBox->addItem(netInterface.humanReadableName());
    }
    // 获取当前下拉框选择的网卡IP等信息
    {
        int currentIndex = m_netCardComboBox->currentIndex();
        QNetworkInterface netInterface = m_allInterfaces.at(currentIndex);
        QList<QNetworkAddressEntry> addressEntries = netInterface.addressEntries();
        for (int k = 0; k < addressEntries.size(); ++k) {
            QNetworkAddressEntry entry = addressEntries.at(k);
            if (entry.ip().protocol() == QAbstractSocket::IPv4Protocol) {  // 这里筛选一下IPv4地址
                qDebug() << addressEntries.at(k).ip().toString();
                qDebug() << addressEntries.at(k).netmask().toString();
                qDebug() << addressEntries.at(k).broadcast().toString();
            }
        }
    }
    return 0;
}

三、VC++实现

如果你不是用QT来开发，可以通过调用 Windows API 来实现这个功能：

#include <iostream>
#include <Windows.h>
#include <IPHlpApi.h>
#include <vector>
#include <string>

#pragma comment(lib, "IPHlpApi.lib")

// wchar_t to string
void wcharToString(std::string& szDst, wchar_t *wchar) {
    wchar_t * wText = wchar;
    DWORD dwNum = WideCharToMultiByte(CP_OEMCP, NULL, wText, -1, NULL, 0, NULL, FALSE);  // WideCharToMultiByte的运用
    char *psText;  // psText为char*的临时数组，作为赋值给std::string的中间变量
    psText = new char[dwNum];
    WideCharToMultiByte(CP_OEMCP, NULL, wText, -1, psText, dwNum, NULL, FALSE);  // WideCharToMultiByte的再次运用
    szDst = psText;  // std::string赋值
    delete[]psText;  // psText的清除
}

void GetNetworkAdaptersInfo() {
    ULONG outBufLen = 0;
    GetAdaptersAddresses(AF_UNSPEC, GAA_FLAG_INCLUDE_PREFIX, NULL, NULL, &outBufLen);
    std::vector<BYTE> buffer(outBufLen);
    PIP_ADAPTER_ADDRESSES pAddresses = reinterpret_cast<PIP_ADAPTER_ADDRESSES>(buffer.data());

    if (GetAdaptersAddresses(AF_UNSPEC, GAA_FLAG_INCLUDE_PREFIX, NULL, pAddresses, &outBufLen) == ERROR_SUCCESS) {
        while (pAddresses) {
            std::string strName, strMAC;
            wcharToString(strName, pAddresses->FriendlyName);  // 用户友好的网卡名称
            wchar_t buf[18];
            swprintf_s(buf, sizeof(buf) / sizeof(wchar_t), L"%02X:%02X:%02X:%02X:%02X:%02X",
                pAddresses->PhysicalAddress[0], pAddresses->PhysicalAddress[1], pAddresses->PhysicalAddress[2],
                pAddresses->PhysicalAddress[3], pAddresses->PhysicalAddress[4], pAddresses->PhysicalAddress[5]);
            wcharToString(strMAC, buf);
            std::cout << strName << std::endl;
            std::cout << strMAC << std::endl;
            pAddresses = pAddresses->Next;
        }
    }
}