qt 使用 winhttp demo

以下是使用 WinHTTP 在 Qt 中进行 HTTP 请求的示例代码：

#include <QCoreApplication>
#include <QUrl>
#include <QDebug>
#include <QByteArray>
#include <Windows.h>
#include <winhttp.h>

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

int main(int argc, char *argv[])
{
    QCoreApplication a(argc, argv);

    // 创建 WinHTTP 会话
    HINTERNET hSession = WinHttpOpen(L"WinHTTP Example/1.0", WINHTTP_ACCESS_TYPE_DEFAULT_PROXY, WINHTTP_NO_PROXY_NAME, WINHTTP_NO_PROXY_BYPASS, 0);
    if (!hSession)
    {
        qDebug() << "WinHttpOpen failed: " << GetLastError();
        return -1;
    }

    // 创建 HTTP 连接
    QUrl url("http://www.example.com");
    HINTERNET hConnect = WinHttpConnect(hSession, reinterpret_cast<const wchar_t*>(url.host().utf16()), url.port() == -1 ? INTERNET_DEFAULT_HTTP_PORT : url.port(), 0);
    if (!hConnect)
    {
        WinHttpCloseHandle(hSession);
        qDebug() << "WinHttpConnect failed: " << GetLastError();
        return -1;
    }

    // 创建 HTTP 请求
    HINTERNET hRequest = WinHttpOpenRequest(hConnect, L"GET", reinterpret_cast<const wchar_t*>(url.path().utf16()), L"HTTP/1.1", WINHTTP_NO_REFERER, WINHTTP_DEFAULT_ACCEPT_TYPES, WINHTTP_FLAG_REFRESH);
    if (!hRequest)
    {
        WinHttpCloseHandle(hConnect);
        WinHttpCloseHandle(hSession);
        qDebug() << "WinHttpOpenRequest failed: " << GetLastError();
        return -1;
    }

    // 发送 HTTP 请求
    if (!WinHttpSendRequest(hRequest, WINHTTP_NO_ADDITIONAL_HEADERS, 0, WINHTTP_NO_REQUEST_DATA, 0, 0, 0))
    {
        WinHttpCloseHandle(hRequest);
        WinHttpCloseHandle(hConnect);
        WinHttpCloseHandle(hSession);
        qDebug() << "WinHttpSendRequest failed: " << GetLastError();
        return -1;
    }

    // 等待响应
    if (!WinHttpReceiveResponse(hRequest, 0))
    {
        WinHttpCloseHandle(hRequest);
        WinHttpCloseHandle(hConnect);
        WinHttpCloseHandle(hSession);
        qDebug() << "WinHttpReceiveResponse failed: " << GetLastError();
        return -1;
    }

    // 读取响应数据
    QByteArray responseData;
    DWORD dwSize = 0;
    do
    {
        char szData[1024] = { 0 };
        if (!WinHttpReadData(hRequest, szData, sizeof(szData) - 1, &dwSize))
        {
            WinHttpCloseHandle(hRequest);
            WinHttpCloseHandle(hConnect);
            WinHttpCloseHandle(hSession);
            qDebug() << "WinHttpReadData failed: " << GetLastError();
            return -1;
        }
        responseData.append(szData, static_cast<int>(dwSize));
    } while (dwSize > 0);

    // 输出响应数据
    qDebug() << responseData;

    // 关闭 WinHTTP 相关句柄
    WinHttpCloseHandle(hRequest);
    WinHttpCloseHandle(hConnect);
    WinHttpCloseHandle(hSession);

    return a.exec();
}

在这个示例中，我们使用 WinHTTP 创建了一个 HTTP 会话、连接和请求，并发送了一个 GET 请求以获取 http://www.example.com 的响应数据。请注意，这个示例并没有处理任何错误或异常情况，你需要根据你的实际需求进行扩展和改进。