在 C# 中重用 HttpWebRequest 的连接

Question

我需要使用 .Net 发出 POST 请求。

我可以通过 GET 进行身份验证，因此我尝试在同一连接上发出 POST 请求以保持身份验证。

问题是我收到 401 Not Authenticated 异常，这意味着连接尚未被重用。

HttpWebRequest request = (HttpWebRequest)WebRequest.Create("my-server");
request.Credentials = new NetworkCredential("user", "password");

request.GetResponse().Close();  // Works fine

// Now the request I want to make...

request = (HttpWebRequest)WebRequest.Create("my-server");
request.Credentials = new NetworkCredential("user", "password");

request.Method = "post";

string postData = "param1=1&param2=2";
byte[] data = new ASCIIEncoding().GetBytes(postData);
request.ContentLength = data.Length;
request.ContentType = "application/x-www-form-urlencoded";

using (Stream stream = request.GetRequestStream())
{
    stream.Write(data, 0, data.Length);
    stream.Close();
    request.GetResponse().Close();      // This line gets a 401 Not Authorized error.
}

编辑：有人建议我需要传输cookie。以下也不起作用：

HttpWebRequest request = (HttpWebRequest)WebRequest.Create("my-server");
request.Credentials = new NetworkCredential("user", "password");

var response = (HttpWebResponse)request.GetResponse();

var cookieContainer = new CookieContainer();
foreach (Cookie cookie in response.Cookies)
{
    cookieContainer.Add(cookie);
}

response.Close();

// Now the request I want to make...

request = (HttpWebRequest)WebRequest.Create("my-server");
request.Credentials = new NetworkCredential("user", "password");
request.CookieContainer = cookieContainer;

request.Method = "post";

string postData = "param1=1&param2=2";
byte[] data = new ASCIIEncoding().GetBytes(postData);
request.ContentLength = data.Length;
request.ContentType = "application/x-www-form-urlencoded";

using (Stream stream = request.GetRequestStream())
{
    stream.Write(data, 0, data.Length);
    request.GetResponse().Close();      // This line gets a 401 Not Authorized error.
}

Answer 1

您不保持登录状态的原因是您没有为 HttpWebRequest 提供 CookieContainer 来保存会话 id。

请参阅以下 StackOverflow 问答以获取可能的解决方案：

C# 通过 httpwebrequest 保留会话 ID

同一会话中的多个 WebRequest

我希望这会有所帮助。

Answer 2

知道另一端如何管理身份验证吗？ IE。如果它设置了 cookie，那么您需要确保对此进行解释，请参阅此 页面，特别是此注释：

注意

出于安全原因，默认情况下禁用 cookie。如果您想使用 cookie，请使用 CookieContainer 属性启用 cookie。