三层架构求教！！！

Question

哪位大虾跟小弟我讲一下c#三层架构????

Answer 1

数据数据访问层
using System;
using System.Collections.Generic;
using System.Text;
using System.Data;
using System.Data.SqlClient;namespace Employee
{
    class EmployeeDAO
    {
        static private string GetConnectionString()
        {
            // To avoid storing the connection string in your code, 
            // you can retrieve it from a configuration file.
            return "Data Source=localhost;Initial Catalog=employee;Persist Security Info=True;User ID=sa;Password=111111";
        }
        static public void InsertEmployee(Employee employee)
        {            string connectionString = GetConnectionString();
            string queryString =
                "insert into employee (name,sex,salary) values('"+employee.Name+"','"+employee.Sex+"',"+employee.Salary+")";
            SqlConnection connection =
                   new SqlConnection(connectionString);            SqlCommand command = connection.CreateCommand();
            command.CommandText = queryString;            try
            {
                connection.Open();                command.ExecuteNonQuery();
                connection.Close();            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
        }        static public List<Employee> GetAll()
        {
            List<Employee> employeeList = new List<Employee>();
            string connectionString = GetConnectionString();
            string queryString =
                "select * from employee";
            SqlConnection connection =
                   new SqlConnection(connectionString);            SqlCommand command = connection.CreateCommand();
            command.CommandText = queryString;            try
            {
                connection.Open();
                SqlDataReader reader = command.ExecuteReader();                while (reader.Read())
                {
                    Employee employee = new Employee();
                    employee.Name = reader["name"].ToString();
                    employee.Id = reader["id"].ToString();
                    employee.Sex = reader["sex"].ToString();
                    employeeList.Add(employee);
                }
                reader.Close();            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
            return employeeList;
        }
    }
}业务逻辑层
using System;
using System.Collections.Generic;
using System.Text;namespace Employee
{
    class EmployeeBLL
    {
        static public List<Employee> GetAll()
        {
            List<Employee> empList = new List<Employee>();
            empList = EmployeeDAO.GetAll();            return empList;
        }        static public void insertEmployee(String name, String sex)
        {
            Employee employee = new Employee();
            employee.Name = name;
            employee.Sex = sex;            EmployeeDAO.InsertEmployee(employee);
        }
        //
        static public float getSalary(Employee emp)
        {
            float salary=0;
            return salary;        }
    }
}表示层
using System;
using System.Collections.Generic;
using System.Text;namespace Employee
{
    class Employee
    {
        private String name;        public String Name
        {
            get { return name; }
            set { name = value; }
        }
        private String id;        public String Id
        {
            get { return id; }
            set { id = value; }
        }        private String sex;        public String Sex
        {
            get { return sex; }
            set { sex = value; }
        }        private float salary;        public float Salary
        {
            get { return salary; }
            set { salary = value; }
        }
    }
}

Answer 2

你们说的都是逻辑上的三层，只是将代码分开来写而已，这就是所谓的三层(DAL,BLL,UI)？有没有想过物理上面的三层呢？

Answer 3

Model DAL BLL三层，即model层来封装实体对象、DAL完成业务逻辑处理、BLL又来传值， aspx充当view层。但我们通常将Model和DAL层和为一层，摒弃BLL层

Answer 4

数据访问层——业务逻辑层——表现层，业务逻辑层调用数据访问层，表现层调用业务逻辑层，三层架构中层的耦合度较高，你可以学习一下MVC

Answer 5

http://download.csdn.net/detail/swarb/3851428这有个demo ,自己看下吧

Answer 6

MVC就是典型的三层架构
Model、View、Controller