一个简单的三层架构登陆

数据访问层UserDAL

  public SqlConnection GetConnetion()   //定义连接方法

   {        string myStr = "/*数据库连接*/";

        SqlConnection myConn = new SqlConnection(myStr); //定义连接对象

        myConn.Open();

        return myConn;

    }

public bool ExSql(string Sql_Str) 根据SQL语句执行数据库操作的方法

 {

        bool flag = false;

        SqlConnection myConn = GetConnetion();

        SqlCommand myComm = new SqlCommand(Sql_Str, myConn);

        object result = myComm.ExecuteScalar();

        if (result != null)

        {

            flag = true;

        }

        myConn.Close();

        myComm.Dispose();

        return flag;

    }

业务逻辑层UserBLL

  UserADL aa = new UserADL();

public bool Login(string name, string password)//判断用户名、密码是否正确。正确则跳转到指定页面，

    {

        string mysql = "select * from tb_User where name='" + name + "'and password='" + password + "'";

        aa.Ds(mysql);

        bool flag = false;

        if (aa.ExSql(mysql))

        {

            flag = true;

        }

        return flag;

    }

表示层UserUI

     string name = TextBox1.Text.Trim().ToString();

        string psw = TextBox2.Text.Trim().ToString();

        bool re = aa.Login(name, psw);

        if (name == "" || psw == "")

        {

            Response.Write("<script>alert(不能为空，请输入)</script>");

        }

        else

        {

            if (re)

            {

                    Response.Write("<script>alert('登录成功)</script>");

                    Response.Redirect("admin.aspx?Name="+name);

            }

            else

                Response.Write("<script>alert('烧吕！您的账号或密码不正确！请再次输入')</script>");

        }

    }

第一次写博客！不好莫怪！