Question

看看这个功能：

string PostFile(string link, string filename, string postfilename){
    CURL *curl;
    CURLcode res;
    string readBuffer;

    struct curl_httppost *formpost = NULL;
    struct curl_httppost *lastptr = NULL;
    struct curl_slist *headerlist = NULL;
    static const char buf[] = "Expect :";

    curl_global_init(CURL_GLOBAL_ALL);

    curl_formadd(&formpost,
               &lastptr,
               CURLFORM_COPYNAME, postfilename.c_str(),
               CURLFORM_FILE, filename.c_str(),
               CURLFORM_END);

    curl_formadd(&formpost,
               &lastptr,
               CURLFORM_COPYNAME, "filename",
               CURLFORM_COPYCONTENTS, filename.c_str(),
               CURLFORM_END);

    curl = curl_easy_init();
    headerlist = curl_slist_append(headerlist, buf);

    if(!curl) return "Error";

    curl_easy_setopt(curl, CURLOPT_URL, link.c_str());
    curl_easy_setopt(curl, CURLOPT_HTTPPOST, formpost);
    curl_easy_setopt(curl, CURLOPT_HTTPHEADER, headerlist);
    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, WriteCallback);
    curl_easy_setopt(curl, CURLOPT_WRITEDATA, &readBuffer);

    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_formfree(formpost);
    curl_slist_free_all (headerlist);

    return readBuffer;

}

使用后

PostFile("http://ilovedyourmother.ga/data/test/upload.php", "LOL.txt", "uploadfile");

它会像这样返回错误

curl_easy_perform() failed: Failed to open/read local data from file/application

这个函数基于curl postit2.c示例（http://curl.haxx.se/libcurl/c/postit2.html），实际上我不太明白它是如何工作的。请在这段代码中找到错误或者至少解释一下它的作用。

Answer 1

我遇到了同样的问题。指定CURLFORM_FILE的绝对路径并在此之后添加CURLFORM_FILENAME选项并仅为该选项提供文件名，如下所示。

curl_formadd(&formpost,
             &lastptr,
             CURLFORM_COPYNAME, "image_data",
             CURLFORM_FILE, "/home/user/TestImages/123.jpg",
             CURLFORM_FILENAME, "123.jpg",
             CURLFORM_CONTENTTYPE, "image/jpeg",
             CURLFORM_END);

Curl（C ++）错误：无法上传文件

1 个答案: