.NET三层架构实现用户登录验证

用三层架构实现的登录验证的demo,适合新手使用，条理清晰，一看就会。

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

namespace Business
{
    public class User
    {
        DataAccess.GetData GD = new DataAccess.GetData（）;
        #region 属性
        /// 

        /// ID
        /// 

        public string ID
        {
            get;
            set;
        }
        /// 

        /// 姓名
        /// 

        public string Name
        {
            get;
            set;
        }
        /// 

        /// 密码
        /// 

        public string PassWord
        {
            get;
            set;
        }

        #endregion

        #region 方法
        public DataTable Login（User loginUser） 
        {
           DataTable loginuserdata = GD.GetDataTable（“select * from Users where ID = ‘“ + loginUser.ID +“‘ and PassWord = ‘“+ loginUser.PassWord +“‘“）;
           return loginuserdata; 
        }
        #endregion
    }
}

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----
     目录           0  2014-10-24 22:29  test\
     目录           0  2014-10-24 22:40  test\Business\
     目录           0  2014-10-24 22:40  test\Business\bin\
     目录           0  2014-10-24 23:25  test\Business\bin\Debug\
     文件        5120  2014-10-24 23:25  test\Business\bin\Debug\Business.dll
     文件       11776  2014-10-24 23:25  test\Business\bin\Debug\Business.pdb
     文件       17920  2014-10-24 23:25  test\Business\bin\Debug\DataAccess.dll
     文件       32256  2014-10-24 23:25  test\Business\bin\Debug\DataAccess.pdb
     目录           0  2014-10-24 22:40  test\Business\bin\Release\
     文件        2520  2014-10-24 23:25  test\Business\Business.csproj
     目录           0  2014-10-24 22:29  test\Business\obj\
     目录           0  2014-10-24 23:25  test\Business\obj\Debug\
     文件         359  2014-10-24 23:25  test\Business\obj\Debug\Business.csproj.FileListAbsolute.txt
     文件        6557  2014-10-24 23:25  test\Business\obj\Debug\Business.csprojResolveAssemblyReference.cache
     文件        5120  2014-10-24 23:25  test\Business\obj\Debug\Business.dll
     文件       11776  2014-10-24 23:25  test\Business\obj\Debug\Business.pdb
     文件        5702  2014-10-24 23:25  test\Business\obj\Debug\DesignTimeResolveAssemblyReferencesInput.cache
     目录           0  2014-10-24 22:29  test\Business\obj\Debug\TempPE\
     目录           0  2014-10-24 22:29  test\Business\Properties\
     文件        1348  2014-10-24 22:29  test\Business\Properties\AssemblyInfo.cs
     文件        1045  2014-10-24 23:05  test\Business\User.cs
     目录           0  2014-10-24 22:33  test\DataAccess\
     目录           0  2014-10-24 22:30  test\DataAccess\bin\
     目录           0  2014-10-24 23:25  test\DataAccess\bin\Debug\
     文件       17920  2014-10-24 23:25  test\DataAccess\bin\Debug\DataAccess.dll
     文件       32256  2014-10-24 23:25  test\DataAccess\bin\Debug\DataAccess.pdb
     目录           0  2014-10-24 22:30  test\DataAccess\bin\Release\
     文件       29107  2014-10-24 23:09  test\DataAccess\DataAccess.cs
     文件        2312  2014-10-24 23:25  test\DataAccess\DataAccess.csproj
     目录           0  2014-10-24 22:28  test\DataAccess\obj\
     目录           0  2014-10-24 23:25  test\DataAccess\obj\Debug\
............此处省略67个文件信息