写一个c++ http请求程序

以下是一个简单的 C++ HTTP 请求程序示例，使用 WinHTTP 库发送 GET 请求。本示例仅供参考，实际使用中可能需要根据具体情况进行修改和调整。

#include <iostream>
#include <Windows.h>
#include <winhttp.h>

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

int main(int argc, char* 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)
    {
        std::cerr << "Failed to open WinHTTP session" << std::endl;
        return 1;
    }

    // 创建 HTTP 连接
    HINTERNET hConnect = WinHttpConnect(hSession, L"www.example.com", INTERNET_DEFAULT_HTTP_PORT, 0);
    if (!hConnect)
    {
        std::cerr << "Failed to connect to server" << std::endl;
        WinHttpCloseHandle(hSession);
        return 2;
    }

    // 创建 HTTP 请求
    HINTERNET hRequest = WinHttpOpenRequest(hConnect, L"GET", L"/", NULL, WINHTTP_NO_REFERER, WINHTTP_DEFAULT_ACCEPT_TYPES, 0);
    if (!hRequest)
    {
        std::cerr << "Failed to create HTTP request" << std::endl;
        WinHttpCloseHandle(hConnect);
        WinHttpCloseHandle(hSession);
        return 3;
    }

    // 发送 HTTP 请求
    if (!WinHttpSendRequest(hRequest, WINHTTP_NO_ADDITIONAL_HEADERS, 0, WINHTTP_NO_REQUEST_DATA, 0, 0, 0))
    {
        std::cerr << "Failed to send HTTP request" << std::endl;
        WinHttpCloseHandle(hRequest);
        WinHttpCloseHandle(hConnect);
        WinHttpCloseHandle(hSession);
        return 4;
    }

    // 等待响应
    if (!WinHttpReceiveResponse(hRequest, NULL))
    {
        std::cerr << "Failed to receive HTTP response" << std::endl;
        WinHttpCloseHandle(hRequest);
        WinHttpCloseHandle(hConnect);
        WinHttpCloseHandle(hSession);
        return 5;
    }

    // 读取响应数据
    DWORD dwSize = 0;
    DWORD dwDownloaded = 0;
    LPSTR pszOutBuffer;
    do
    {
        // 确定缓冲区大小
        dwSize += 4096;
        pszOutBuffer = new char[dwSize];

        // 读取数据
        if (!WinHttpReadData(hRequest, (LPVOID)pszOutBuffer, 4096, &dwDownloaded))
        {
            std::cerr << "Failed to read HTTP response data" << std::endl;
            WinHttpCloseHandle(hRequest);
            WinHttpCloseHandle(hConnect);
            WinHttpCloseHandle(hSession);
            delete[] pszOutBuffer;
            return 6;
        }
        else
        {
            // 输出数据
            std::cout << pszOutBuffer;
        }

        // 释放缓冲区
        delete[] pszOutBuffer;

    } while (dwDownloaded > 0);

    // 关闭请求、连接和会话句柄
    WinHttpCloseHandle(hRequest);
    WinHttpCloseHandle(hConnect);
    WinHttpCloseHandle(hSession);

    return 0;
}

在本示例中，首先创建了 WinHTTP 会话，然后创建了 HTTP 连接和 HTTP 请求。接着，发送 HTTP 请求，并等待响应。最后，读取响应数据并输出。注意，在实际使用中，需要根据具体情况设置 HTTP 请求的方法、URL、请求头、请求数据等参数。