c++http客户端发送怎么写

Question

就是我想用c++的http进行发送数据，比如说像http://127.0.0.1:7999/api/fun1发送数据，应该怎么写我看别人写的使用#include <wininet.h>，#include <json/json.h>这两个，代码

#include <windows.h>
#include <wininet.h>
#include <json/json.h>
#include <iostream>
using namespace Json;
#pragma comment(lib, "wininet.lib")

int main() {
    HINTERNET hInternet, hConnect;
    DWORD bytesRead;
    char buffer[4096];

    // 初始化WinINet库
    hInternet = InternetOpenA("MyApp", INTERNET_OPEN_TYPE_DIRECT, NULL, NULL, 0);
    if (hInternet == NULL) {
        std::cerr << "InternetOpenA failed!" << std::endl;
        return 1;
    }

    // 打开HTTP连接
    hConnect = InternetOpenUrlA(hInternet, "http://127.0.0.1:7999/api/fun1", NULL, 0, INTERNET_FLAG_RELOAD, 0);
    if (hConnect == NULL) {
        std::cerr << "InternetOpenUrlA failed!" << std::endl;
        InternetCloseHandle(hInternet);
        return 1;
    }

    // 构建JSON数据
    Json::Value jsonData;
    jsonData["key1"] = "value1";
    jsonData["key2"] = "value2";
    std::string postData = jsonData.toStyledString();

    // 发送POST数据
// 发送POST数据
    if (!InternetWriteFile(hConnect, postData.c_str(), postData.length(), &bytesRead)) {
        DWORD error = GetLastError();
        char errorBuffer[4096];
        DWORD bufferSize = sizeof(errorBuffer);
        if (InternetGetLastResponseInfoA(&error, errorBuffer, &bufferSize)) {
            std::cerr << "InternetWriteFile failed! Error: " << error << ", Response: " << errorBuffer << std::endl;
        }
        else {
            std::cerr << "InternetWriteFile failed! Error: " << error << std::endl;
        }
        InternetCloseHandle(hConnect);
        InternetCloseHandle(hInternet);
        return 1;
    }


    // 读取响应数据
    while (InternetReadFile(hConnect, buffer, sizeof(buffer), &bytesRead) && bytesRead > 0) {
        // 在这里处理响应数据，例如打印到控制台
        std::cout.write(buffer, bytesRead);
    }

    // 关闭连接和WinINet库
    InternetCloseHandle(hConnect);
    InternetCloseHandle(hInternet);

    return 0;
}

使用这个发送的时候，报错的是InternetWriteFile failed! Error，但是服务器那边接受到了数据，只是没有消息体，并且使用postman是可以发送成功的，应该怎么修改

Answer 1

#include <iostream>
#include <string>
#include <curl/curl.h>

size_t WriteCallback(void *contents, size_t size, size_t nmemb, std::string *s) {
    size_t newLength = s->length() + size*nmemb;
    char *newStr = new char[newLength];
    delete[] s->data();
    s->assign(newStr, newLength);
    return size*nmemb;
}

int main(void) {
    CURL *curl;
    CURLcode res;
    std::string s = "";

    curl_global_init(CURL_GLOBAL_DEFAULT);
    curl = curl_easy_init();
    if(curl) {
        curl_easy_setopt(curl, CURLOPT_URL, "http://example.com"); // 修改为你的URL
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, WriteCallback);
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &s);
        res = curl_easy_perform(curl);
        if(res != CURLE_OK) {
            fprintf(stderr, "curl_easy_perform() failed: %s\n", curl_easy_strerror(res));
        }
        curl_easy_cleanup(curl);
    }
    curl_global_cleanup();

    std::cout << s << std::endl;
    return 0;
}