#include <stdio.h>
#include <curl/curl.h>int main(void)
{CURL* curl = NULL;CURLcode res;curl = curl_easy_init();if(curl == NULL) {return CURLE_FAILED_INIT;}struct curl_slist* headerlist = NULL; // 设置表头，表头内容可能不同headerlist = curl_slist_append(headerlist, "Content-Type:application/x-www-form-urlencoded");curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headerlist);  // 设置URLcurl_easy_setopt(curl, CURLOPT_URL, "http://postit.example.com/moo.cgi");// 设置参数，比如"ParamName1=ParamName1Content&ParamName2=ParamName2Content&..."curl_easy_setopt(curl, CURLOPT_POSTFIELDS, "name=daniel&project=curl");// 设置为Postcurl_easy_setopt(curl, CURLOPT_POST, 1);// 发送res = curl_easy_perform(curl);if(res != CURLE_OK){// 获取详细错误信息char* szErr = curl_easy_strerror(res);fprintf(stderr, "curl_easy_perform() failed: %s\n", szErr);}// 清空
    curl_easy_cleanup(curl);// 释放表头
    curl_slist_free_all (headerlist);  return 0;
}

#include <stdio.h>
#include <curl/curl.h>size_t OnWriteData(void* buffer, size_t size, size_t nmemb, void* lpVoid);int main(void)
{CURL* curl = NULL;CURLcode res;curl = curl_easy_init();if(curl == NULL) {return CURLE_FAILED_INIT;}struct curl_slist*        headerlist    = NULL; struct curl_httppost*    formpost    = NULL;struct curl_httppost*    lastptr        = NULL;std::string strResponse;    // 回复
 curl_formadd(&formpost, &lastptr, CURLFORM_COPYNAME, "ParamName1", CURLFORM_COPYCONTENTS, "ParamName1Content", CURLFORM_END);curl_formadd(&formpost, &lastptr, CURLFORM_COPYNAME, "ParamName2", CURLFORM_COPYCONTENTS, "ParamName2Content", CURLFORM_END);curl_formadd(&formpost, &lastptr, CURLFORM_COPYNAME, "ParamName3", CURLFORM_COPYCONTENTS, "ParamName3Content", CURLFORM_END);curl_formadd(&formpost, &lastptr, CURLFORM_COPYNAME, "registerImgs", CURLFORM_FILE, "C:/Image.png", CURLFORM_END);    // 设置要上传的文件// 设置表单参数
    curl_easy_setopt(curl, CURLOPT_HTTPPOST, formpost);// 设置表头，表头内容可能不同headerlist = curl_slist_append(headerlist, "Content-Type:application/x-www-form-urlencoded");curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headerlist);  // 设置URLcurl_easy_setopt(curl, CURLOPT_URL, "http://postit.example.com/moo.cgi");// 设置参数，比如"ParamName1=ParamName1Content&ParamName2=ParamName2Content&..."curl_easy_setopt(curl, CURLOPT_POSTFIELDS, "name=daniel&project=curl");// 设置为Postcurl_easy_setopt(curl, CURLOPT_POST, 1);curl_easy_setopt(curl, CURLOPT_READFUNCTION, NULL);curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, OnWriteData);curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void*)&strResponse);curl_easy_setopt(curl, CURLOPT_NOSIGNAL, 1);curl_easy_setopt(curl, CURLOPT_CONNECTTIMEOUT, 3);curl_easy_setopt(curl, CURLOPT_TIMEOUT, 3);// 发送res = curl_easy_perform(curl);if(res != CURLE_OK){// 获取详细错误信息char* szErr = curl_easy_strerror(res);fprintf(stderr, "curl_easy_perform() failed: %s\n", szErr);}// 清空
    curl_easy_cleanup(curl);// 释放表单
    curl_formfree(formpost);// 释放表头
    curl_slist_free_all (headerlist);  return 0;
}size_t OnWriteData(void* buffer, size_t size, size_t nmemb, void* lpVoid)
{std::string* str = dynamic_cast<std::string*>((std::string *)lpVoid);if( NULL == str || NULL == buffer ){return -1;}char* pData = (char*)buffer;str->append(pData, size * nmemb);return nmemb;
}