测试类：（ConnectionFactoryFixture.cs） 主要测试了CreateConnection这个方法的逻辑分支，以及抛出的各种异常。

using System;
using System.Text;
using System.Collections.Generic;
using NUnit.Framework;
using Microsoft.Practices.SmartClient.ConnectionMonitor.Implementations;
namespace Microsoft.Practices.SmartClient.ConnectionMonitor.Tests
{
    /// <summary>
    /// Summary description for ConnectionFactoryFixture
    /// </summary>
    [TestFixture]
    public class ConnectionFactoryFixture
    {
        public ConnectionFactoryFixture()
        {
        }

        [Test]
        public void CanCreateDesktopConnection()
        {
            Connection connection = ConnectionFactory.CreateConnection("DesktopConnection"， 1);
            Assert.IsNotNull(connection);
            Assert.IsTrue(connection is DesktopConnection);
        }

        [Test]
        public void CanCreateNicConnection()
        {
            Connection connection = ConnectionFactory.CreateConnection("NicConnection"， 1);
            Assert.IsNotNull(connection);
            Assert.IsTrue(connection is NicConnection);
        }


        [Test]
        public void CanCreateWirelessConnection()
        {
            Connection connection = ConnectionFactory.CreateConnection("WirelessConnection"， 1);
            Assert.IsNotNull(connection);
            Assert.IsTrue(connection is WirelessConnection);
        }


        [Test]
        public void CanCreateWiredConnection()
        {
            Connection connection = ConnectionFactory.CreateConnection("WiredConnection"， 1);
            Assert.IsNotNull(connection);
            Assert.IsTrue(connection is WiredConnection);
        }

        [Test]
        public void CanCreateMyCustomConnection()
        {
            Connection connection = ConnectionFactory.CreateConnection("Microsoft.Practices.SmartClient.ConnectionMonitor.Tests.MyCustomConnection，SmartClient.ConnectionMonitor.Tests"， 1);
            Assert.IsNotNull(connection);
            Assert.IsTrue(connection is MyCustomConnection);
        }
       
        [Test]
        [ExpectedException(typeof(ConnectionMonitorException))]
        public void CreateConnectionThrowsWhenPassedBadType()
        {
            Connection connection = ConnectionFactory.CreateConnection("BadTypeName"， 1);
        }
       
        [Test]
        [ExpectedException(typeof(ArgumentNullException))]
        public void CreateConnectionThrowsWhenPassedNullType()
        {
            Connection connection = ConnectionFactory.CreateConnection(null， 1);
        }

        [Test]
        [ExpectedException(typeof(ArgumentException))]
        public void CreateConnectionThrowsWhenPassedEmptyType()
        {
            Connection connection = ConnectionFactory.CreateConnection(String.Empty， 1);
        }

        [Test]
        [ExpectedException(typeof(ArgumentOutOfRangeException))]
        public void CreateConnectionThrowsWhenPassedNegativePrice()
        {
            Connection connection = ConnectionFactory.CreateConnection("WiredConnection"， -1);
        }

    }
}