将文件发送到 HTTP 服务器（C++ Wininet）

Question

我有用于在我的 HTTP 服务器上上传小型 .txt 文件的代码：

#include <wininet.h>
#define BUF_SIZE 4096

void __fastcall TForm1::Button1Click(TObject *Sender)
{

 TStringList * list = new TStringList();
 AnsiString Path = "";

 if(OpenDialog1->Execute()) {

    Path =  "filename=\""+OpenDialog1->FileName+"\"";
    list->LoadFromFile(OpenDialog1->FileName);

 }

 char data[BUF_SIZE] = "";
 static char hdrs[] = "Content-Type: multipart/form-data; boundary=---------------------------7d82751e2bc0858";

 strcat(data,"-----------------------------7d82751e2bc0858");
 strcat(data,"\n");
 strcat(data,"Content-Disposition: form-data; name=\"files[]\"; ");
 strcat(data,Path.c_str());
 strcat(data,"\n");
 strcat(data,"Content-Type: application/octet-stream");
 strcat(data,"\n\n");
 strcat(data,list->Text.c_str());
 strcat(data,"\n");
 strcat(data,"-----------------------------7d82751e2bc0858");
 strcat(data,"\n");
 strcat(data,"Content-Disposition: form-data; name=\"user\"");
 strcat(data,"\r\n\r\n");
 strcat(data,"username");
 strcat(data,"\r\n");
 strcat(data,"-----------------------------7d82751e2bc0858");
 strcat(data,"\n");

 HINTERNET hSession = InternetOpen("MyAgent",INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);
 HINTERNET hConnect = InternetConnect(hSession, "localhost",INTERNET_DEFAULT_HTTP_PORT, NULL, NULL, INTERNET_SERVICE_HTTP, 0, 1);
 HINTERNET hRequest = HttpOpenRequest(hConnect, "POST", "new_upltest.php", NULL, NULL, NULL, 0, 1);

 HttpSendRequest(hRequest, hdrs, strlen(hdrs), data, strlen(data));

 delete list;
}

它工作正常，但现在我需要上传大文件（超过 70-100 mb），可以是图像（.jpg、.png、.bmp）和其他文档类型（.pdf、.docx、等）。

是否可以使用此代码解决我的任务？我将不胜感激每一个建议...

P.S.我的IDE是C++ Builder 6，不过我觉得没关系。

Answer 1

这是一个文件上传的工作示例：

void http_upload_file(PCHAR szServer, PCHAR szScript, PCHAR szParam, PCHAR szValue, PCHAR szFile)
{
    PCHAR szHeaders = "Content-Type: multipart/form-data; boundary=----qwerty";
    PCHAR szData    = "------qwerty\r\n"
                      "Content-Disposition: form-data; name=\"%s\"\r\n\r\n%s\r\n"
                      "------qwerty\r\n"
                      "Content-Disposition: form-data; name=\"files[]\"; filename=\"%s\"\r\n"
                      "Content-Type: application/octet-stream\r\n"
                      "Content-Transfer-Encoding: binary\r\n\r\n";
    PCHAR szDataEnd = "\r\n------qwerty--\r\n";
    char  szHeader[512];

    HINTERNET hSession, hConnect, hRequest;
    DWORD     dwFileSize, dwBytesRead, dwContentLength,dwBytesWritten;

    hSession = InternetOpen(NULL, INTERNET_OPEN_TYPE_DIRECT, NULL, NULL, 0);

    if (hSession)
    {
        hConnect = InternetConnect(hSession, szServer, INTERNET_DEFAULT_HTTP_PORT, NULL, NULL, INTERNET_SERVICE_HTTP,0, 0);

        if (hConnect)
        {
            hRequest = HttpOpenRequest(hConnect, "POST", szScript, NULL, NULL, 0, 0, 0);

            if (hRequest)
            {
                HANDLE hFile = CreateFile(szFile, GENERIC_READ, FILE_SHARE_READ, NULL, OPEN_EXISTING, NULL, NULL);

                if (hFile != INVALID_HANDLE_VALUE)
                {
                    dwFileSize      = GetFileSize(hFile, NULL);
                    wsprintf(szHeader, szData, szParam, szValue, szFile);
                    dwContentLength = lstrlen(szHeader) + dwFileSize + lstrlen(szDataEnd);
                    LPBYTE pBuf     = (LPBYTE)malloc(dwContentLength);
                    CopyMemory(&pBuf[0], szHeader, lstrlen(szHeader));
                    ReadFile(hFile, &pBuf[lstrlen(szHeader)], dwFileSize, &dwBytesRead, NULL);
                    CopyMemory(&pBuf[lstrlen(szHeader) + dwFileSize], szDataEnd, lstrlen(szDataEnd));
                    HttpSendRequest(hRequest, szHeaders, lstrlen(szHeaders), pBuf, dwContentLength);
                    CloseHandle(hFile);
                    free(pBuf);
                }
            }

            InternetCloseHandle(hRequest);
        }

        InternetCloseHandle(hConnect);
    }

    InternetCloseHandle(hSession);
}