SoapHttpClientProtocol缓存代理凭据？

Question

我注意到在.NET4中，SoapHttpClientProtocol似乎缓存了代理凭据。有谁知道这是不是真的，以及如何刷新这个缓存？如果我的用户更改了他们的凭据，我想尝试一下，但是一旦我成功连接到任何SoapHttpClientProtocol，任何对invoke的调用似乎都可以工作。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using System.Web.Services;
    class Program : System.Web.Services.Protocols.SoapHttpClientProtocol
{
    public Program()
    {
        base.Url = "something";
    }
    static void Main(string[] args)
    {
        Program x = new Program();
        x.Proxy = new WebProxy("basicproxy", 2121);
        x.Proxy.Credentials = new NetworkCredential("proxyuser", "IncorrectPassword");
        Console.WriteLine("Attempt with proxyuser and IncorrectPassword: " + x.NoOp());

        x.Proxy.Credentials = new NetworkCredential("proxyuser", "password");
        Console.WriteLine("Attempt with proxyuser and password: " + x.NoOp());

        x.Proxy.Credentials = new NetworkCredential("proxyuser", "IncorrectPassword");
        Console.WriteLine("Attempt with proxyuser and IncorrectPassword: " + x.NoOp());

        Program y = new Program();
        y.Proxy = new WebProxy("basicproxy", 2121);
        y.Proxy.Credentials = new NetworkCredential("proxyuser", "IncorrectPassword");
        Console.WriteLine("Attempt with proxyuser and IncorrectPassword: " + y.NoOp());
    }

    /// <remarks/>
    [System.Web.Services.Protocols.SoapDocumentMethodAttribute("...", RequestNamespace = "...", ResponseNamespace = "...", Use = System.Web.Services.Description.SoapBindingUse.Literal, ParameterStyle = System.Web.Services.Protocols.SoapParameterStyle.Wrapped)]
    public bool NoOp()
    {
        try
        {
            object[] results = this.Invoke("NoOp", new object[0]);
            return ((bool)(results[0]));
        }
        catch (WebException e)
        {
            if (e.Response != null && ((HttpWebResponse)e.Response).StatusCode == HttpStatusCode.ProxyAuthenticationRequired)
            {
                Console.WriteLine("incorrect Credential attempt!");
            }
            else
            {
                Console.WriteLine("Exception: " + e.Message);
            }
        }
        return false;
    }

这个程序的输出(我希望最后两个是false)

incorrect Credential attempt!
Attempt with proxyuser and IncorrectPassword: False
Attempt with proxyuser and password: True
Attempt with proxyuser and IncorrectPassword: True
Attempt with proxyuser and IncorrectPassword: True

Answer 1

使用Reflector快速查看一下HttpWebRequest，就会发现它不会根据代理凭据来区分ServicePoint对象。因此，它为所有这些请求重用相同的http连接池，并且由于相同的连接在第一次成功的代理身份验证后仍然有效，因此它甚至不会尝试使用为最后两个请求提供的凭据。

您可以尝试在设置Proxy属性时将ConnectionGroupName属性设置为包含代理用户名和密码的某个字符串(可能使用帮助器方法)。

另一种选择是对WebProxy构造函数使用proxyuser:password@basicproxy:2121URL方案。