HttpQueryInfo 查询Content-Length
时间: 2023-10-07 20:08:46 浏览: 117
HttpQueryInfo函数可以用来查询HTTP请求的头信息,其中Content-Length字段表示HTTP响应正文的长度。可以使用以下代码查询Content-Length:
```
HINTERNET hSession = InternetOpen("MyApp", INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);
HINTERNET hConnect = InternetConnect(hSession, "www.example.com", INTERNET_DEFAULT_HTTP_PORT, NULL, NULL, INTERNET_SERVICE_HTTP, 0, 1);
HINTERNET hRequest = HttpOpenRequest(hConnect, "GET", "/index.html", HTTP_VERSION_1_1, NULL, NULL, INTERNET_FLAG_RELOAD, 1);
HttpSendRequest(hRequest, NULL, 0, NULL, 0);
DWORD dwContentLength = 0;
DWORD dwLengthSize = sizeof(dwContentLength);
HttpQueryInfo(hRequest, HTTP_QUERY_CONTENT_LENGTH | HTTP_QUERY_FLAG_NUMBER, &dwContentLength, &dwLengthSize, NULL);
InternetCloseHandle(hRequest);
InternetCloseHandle(hConnect);
InternetCloseHandle(hSession);
```
其中,HttpQueryInfo的第二个参数HTTP_QUERY_CONTENT_LENGTH表示要查询Content-Length字段,HTTP_QUERY_FLAG_NUMBER表示Content-Length是一个数字类型,查询结果会被放入第三个参数dwContentLength中。