如何为测试目的模拟网络故障(在C#中)？

我正在为一个新应用程序构建可称为DAL的东西.不幸的是,与数据库的网络连接是一个真正的问题.

我希望能够在我的测试范围内临时阻止网络访问,以便我可以确保我的DAL在这些情况下按预期运行.

更新:有许多手动方式来禁用网络,但如果我可以在测试中启用/禁用它肯定会很好.

目前,我只是通过设置虚假静态IP来"禁用"网络,如下所示:

using System.Management;

class NetworkController
{

    public static void Disable()
    {
        SetIP("192.168.0.4", "255.255.255.0");
    }

    public static void Enable()
    {
        SetDHCP();
    }


    private static void SetIP(string ip_address, string subnet_mask)
    {
        ManagementClass objMC = new ManagementClass("Win32_NetworkAdapterConfiguration");
        ManagementObjectCollection objMOC = objMC.GetInstances();

        foreach (ManagementObject objMO in objMOC) {
            if ((bool)objMO("IPEnabled")) {
                try {
                    ManagementBaseObject setIP = default(ManagementBaseObject);
                    ManagementBaseObject newIP = objMO.GetMethodParameters("EnableStatic");

                    newIP("IPAddress") = new string[] { ip_address };
                    newIP("SubnetMask") = new string[] { subnet_mask };

                    setIP = objMO.InvokeMethod("EnableStatic", newIP, null);
                }
                catch (Exception generatedExceptionName) {
                    throw;
                }
            }


        }
    }

    private static void SetDHCP()
    {
        ManagementClass mc = new ManagementClass("Win32_NetworkAdapterConfiguration");
        ManagementObjectCollection moc = mc.GetInstances();

        foreach (ManagementObject mo in moc) {
            // Make sure this is a IP enabled device. Not something like memory card or VM Ware
            if ((bool)mo("IPEnabled")) {
                ManagementBaseObject newDNS = mo.GetMethodParameters("SetDNSServerSearchOrder");
                newDNS("DNSServerSearchOrder") = null;
                ManagementBaseObject enableDHCP = mo.InvokeMethod("EnableDHCP", null, null);
                ManagementBaseObject setDNS = mo.InvokeMethod("SetDNSServerSearchOrder", newDNS, null);
            }
        }
    }
}

写一个包装器到你正在使用的网络类连接类(例如WebClient)和一个开关开关:)

要么是这样,要么阻止你的应用程序在防火墙中.

如果您正在为应用程序尝试完全网络中断,则可以拔下网络电缆.有时您可能拥有一个包含多个数据源的数据访问层(在不同的计算机上),在这种情况下,您可以使用像Rhino Mocks这样的模拟框架模拟测试中的异常.以下是您可能在测试中使用的一些伪代码

void TestUserDBFailure()
{
    // ***** THIS IS PSEUDO-CODE *******
    //setting up the stage - retrieval of the user info create an exception
    Expect.Call(_userRepository.GetUser(null))
       .IgnoreArguments()
       .Return(new Exception());

    // Call that uses the getuser function, see how it reacts
    User selectedUser = _dataLoader.GetUserData("testuser", "password");        
}