HttpSendRequest 截断我的值，而 HttpSendRequest 按预期工作

Question

我想使用 HttpSendRequest 在 C++ 中发送一个 POST 值。我在 https://requestbin.net 上测试请求我制作了这段代码：

void sendValue()
{
    LPCSTR header = "Content-Type: application/x-www-form-urlencoded; charset=utf-8";
    std::string dataStr = u8"result=a very longue value !!!!!!!!!!!!!!!!!!!!!!!!!!!! :)";
    LPVOID myMessage = (LPVOID)dataStr.c_str();
    HINTERNET hInternet = InternetOpenA("InetURL/1.0", INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);
    HINTERNET hConnection = InternetConnectA(hInternet, "requestbin.net", 80, " ", " ", INTERNET_SERVICE_HTTP, 0, 1);
    HINTERNET hRequest = HttpOpenRequestA(hConnection, "POST", "/r/IDREQUESTBIN", NULL, NULL, NULL, 0, 1);
    HttpSendRequestA(hRequest, header, strlen(header), myMessage, dataStr.size());
    std::cout << "wcslen(header) " << strlen(header) << std::endl;
    std::cout << "dataStr.size() " << dataStr.size() << std::endl;
}

完美运行。我现在想使用 wstring，我编写了这段代码：

void sendValueV2()
{
    LPCWSTR header = L"Content-Type: application/x-www-form-urlencoded; charset=utf-8";
    std::wstring dataStr = L"result=a very longue value !!!!!!!!!!!!!!!!!!!!!!!!!!!! :)";
    LPVOID myMessage = (LPVOID)dataStr.c_str();
    HINTERNET hInternet = InternetOpen(L"InetURL/1.0", INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);
    HINTERNET hConnection = InternetConnect(hInternet, L"requestbin.net", 80, L" ", L" ", INTERNET_SERVICE_HTTP, 0, 1);
    HINTERNET hRequest = HttpOpenRequest(hConnection, L"POST", L"/r/IDREQUESTBIN", NULL, NULL, NULL, 0, 1);
    HttpSendRequest(hRequest, header, wcslen(header), myMessage, dataStr.size());
    std::wcout << "wcslen(header) " << wcslen(header) << std::endl;
    std::wcout << "dataStr.size() " << dataStr.size() << std::endl;
}

我的 POST 值被截断为：result=a very longue value !!

这是我的控制台的输出：

wcslen(header) 62
dataStr.size() 58
wcslen(header) 62
dataStr.size() 58

有人可以向我解释发生了什么事吗？我要疯了。

Answer 1

根据documentation，HttpSendRequest的dwOptional参数是以字节表示的，不是字符，所以替换为：

HttpSendRequest(hRequest, header, wcslen(header), myMessage, dataStr.size());

与：

HttpSendRequest(hRequest, header, wcslen(header), myMessage, dataStr.size() * sizeof (WCHAR));

你的问题应该已经解决了。

HttpSendRequest 截断我的值，而 HttpSendRequest 按预期工作

HttpSendRequest trucate my value while HttpSendRequestA works as excepted

c++

post

http

wininet

http-headers