NUnit单元测试下篇TestDriven.NET

　　前面DebugLZQ写了一篇博文，介绍的是如何使用Nunit编写.NET单元测试。但是使用NUnti进行单元测试有一个致命的弱点：无法调试。因为我们的测试本省也是代码，同样我们不能确定我们的代码是对的。这篇博文将以在VS2010下连接数据库并插入一个字段的方法编写单元测试为例，介绍如何使用TestDriven.NET弥补Nunit的这个致命的弱点。

　　示例项目的工程架构如下：

下面给出几个主要类的源码，Person类的代码如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace VS2010建立SQLServer数据库Test
{
    public class Person
    {
        private int id;        
        private string userName;
        private string password;

        public int Id
        {
            get { return id; }
            set { id = value; }
        }

        public string UserName
        {
            get { return userName; }
            set { userName = value; }
        }
        
        public string Password
        {
            get { return password; }
            set { password = value; }
        }
    }
}

数据库连接类Connection源码如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SqlClient;
using System.Configuration;
using System.Windows.Forms;

namespace VS2010建立SQLServer数据库Test
{
    public class Connection
    {
        public static SqlConnection GetConnection()
        {
            string connectionString = @"Data Source=.\SQLEXPRESS;AttachDbFilename=E:\Visual Studio 2010\VS2010建立SQLServer数据库Test\VS2010建立SQLServer数据库Test\Database1.mdf;Integrated Security=True;User Instance=True";
            SqlConnection conn = new SqlConnection(connectionString);

            try
            {
                conn.Open();
            }
            catch
            {
                return null;
            }

            return conn;


        }


    }
}

相应的测试类ConnectionTest如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using System.Data.SqlClient;
using NUnit.Framework;//

namespace VS2010建立SQLServer数据库Test
{
    [TestFixture]
    public  class ConnectionTest
    {
        [Test]
        public void GetConnectionTest()
        {
            SqlConnection conn= Connection.GetConnection();
            Assert.IsNotNull(conn);
        }
    }
}

数据库帮助类：DBHelper如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SqlClient;

namespace VS2010建立SQLServer数据库Test
{
    public  class DBHelper
    {
        public static  void Insert(Person person)
        {
            string sqlstring = "Insert into UserInfo(username,password) values(@username,@password)";

            SqlConnection conn= Connection.GetConnection();
            SqlCommand cmd = new SqlCommand(sqlstring, conn);
            cmd.Parameters.Add("@username", System.Data.SqlDbType.VarChar);
            cmd.Parameters.Add("@password", System.Data.SqlDbType.VarChar);
            cmd.Parameters["@username"].Value = person.UserName;
            cmd.Parameters["@password"].Value = person.Password;

            try
            {
                cmd.ExecuteNonQuery();
            }
            catch
            {
                throw new Exception("unExpected exception!");
            }
            finally
            {
                conn.Close();
            }
        }
        ///
        public static Person GetPersonById(int id)
        {
            string sqlstring = "Select * from UserInfo where id=@id";

            SqlConnection conn = Connection.GetConnection();
            SqlCommand cmd = new SqlCommand(sqlstring, conn);
            cmd.Parameters.Add("@id", System.Data.SqlDbType.Int );

            cmd.Parameters["@id"].Value = id;

            SqlDataReader reader= cmd.ExecuteReader();
            Person person = null;
            if (reader.Read())
            {
                person = new Person() { 
                 Id=id,
                  UserName=reader["UserName"].ToString(),
                   Password=reader["Password"].ToString()                  
                };                
            }
            reader.Close();
            conn.Close();
            return person;
        }
    }
}

针对的表结果如下：

DBHelper的测试类DBHelperTest如下：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using System.Data.SqlClient;

using NUnit.Framework;

namespace VS2010建立SQLServer数据库Test
{
    [TestFixture]
    public class DBHelperTest
    {
        [Test ]
        public void InsertTest()
        {
            Person person = new Person() { 
             UserName="DebugLZQ_A",
              Password="DebugLZQ_A"            
            };

            DBHelper.Insert(person);

            Person personResult=DBHelper.GetPersonById(GetMaxId());

            Assert.AreEqual(person.UserName , personResult.UserName );
        }

        private int GetMaxId()
        {
            string sqlString = "Select max(Id) as maxId from UserInfo";
            SqlConnection conn = Connection.GetConnection();
            SqlCommand cmd = new SqlCommand(sqlString, conn);

            SqlDataReader reader= cmd.ExecuteReader();

            int maxId = 0;
            if (reader.Read())
            {
                maxId = Convert.ToInt32(reader["maxId"]);
            }

            reader.Close();
            conn.Close();
            return maxId;
        }
    }
}