Net学习日记_三层_1_登录页面总结篇

<?xml version="1.0" encoding="utf-8" ?><configuration> ?<connectionStrings> ???<add name="connStr" connectionString="server=PC201609230944\SQL2005;database=HeiMaBlog;user=sa;pwd=123456"/> ?</connectionStrings></configuration>

using System;using System.Collections.Generic;using System.Data;using System.Linq;using System.Text;using System.Threading.Tasks;namespace FLogin.DAL{ ???/// <summary> ???/// DAL-Student ???/// </summary> ???class Student ???{ ???????/// <summary> ???????/// 取得学员列表 ???????/// </summary> ???????/// <returns></returns> ???????public DataTable GetStudents() ???????{ ???????????return SqlHelper.ExecuteDataTable("SELECT * FROM dbo.Student"); ???????} ???}}

using System;using System.Collections.Generic;using System.Data;using System.Data.SqlClient;using System.Linq;using System.Text;using System.Threading.Tasks;namespace FLogin.DAL{ ???class SqlHelper ???{ ???????/// <summary> ???????/// 对配置文件connnectionStrings节进行读取 ???????/// </summary> ???????static string connstr = System.Configuration.ConfigurationManager.ConnectionStrings["connStr"].ConnectionString; ???????/// <summary> ???????/// 查询数据库返回一张表 ???????/// </summary> ???????/// <param name="sql"></param> ???????/// <param name="parameters"></param> ???????/// <returns></returns> ???????public static DataTable ExecuteDataTable(string sql, params SqlParameter[] parameters) ???????{ ???????????// 创建临时数据集，内存。 ???????????DataSet ds = new DataSet(); ???????????// 创建适配器对象 ???????????SqlDataAdapter adapter = new SqlDataAdapter(sql, connstr); ???????????// 给适配器对象的查询命令对象添加参数 ???????????adapter.SelectCommand.Parameters.AddRange(parameters); ???????????try ???????????{ ???????????????// 充填数据集 ???????????????adapter.Fill(ds); ???????????????return ds.Tables[0]; ???????????} ???????????catch ???????????{ ???????????????return null; ???????????} ???????} ???????/// <summary> ???????/// 对数据库进行增，删、该等活动 ???????/// </summary> ???????/// <param name="sql"></param> ???????/// <param name="parameters"></param> ???????/// <returns></returns> ???????public static int ExecuteNonQuery(string sql, params SqlParameter[] parameters) ???????{ ???????????using (SqlConnection conn = new SqlConnection(connstr)) ???????????{ ???????????????using (SqlCommand cmd = new SqlCommand(sql, conn)) ???????????????{ ???????????????????cmd.Parameters.AddRange(parameters); ???????????????????conn.Open(); ???????????????????return cmd.ExecuteNonQuery(); ???????????????} ???????????} ???????} ???????/// <summary> ???????/// 对数据库进行查询 ???????/// </summary> ???????/// <param name="sql"></param> ???????/// <param name="parameters"></param> ???????/// <returns></returns> ???????public static object ExecuteScalar(string sql, params SqlParameter[] parameters) ???????{ ???????????using (SqlConnection conn = new SqlConnection(connstr)) ???????????{ ???????????????using (SqlCommand cmd = new SqlCommand(sql, conn)) ???????????????{ ???????????????????cmd.Parameters.AddRange(parameters); ???????????????????conn.Open(); ???????????????????return cmd.ExecuteScalar(); ???????????????} ???????????} ???????} ???}}

using System;using System.Collections.Generic;using System.Data;using System.Data.SqlClient;using System.Linq;using System.Text;using System.Threading.Tasks;namespace FLogin.DAL{ ???class UserInfo ???{ ???????/// <summary> ???????/// 根据姓名取得用户,得到一行数据集 ???????/// </summary> ???????/// <param name="_name"></param> ???????/// <returns></returns> ???????public DataTable GetUserByName(string _name) ???????{ ???????????return SqlHelper.ExecuteDataTable("SELECT * ,DATEDIFF(MINUTE,LastErrTime,GETDATE())FROM dbo.UserInfo WHERE UserName =@UserName", ???????????????new SqlParameter("@UserName", SqlDbType.NVarChar) { Value = _name}); ???????} ???????/// <summary> ???????/// 重置错误次数 ???????/// </summary> ???????/// <param name="_id"></param> ???????/// <returns></returns> ???????public int ReSetErrTimes(int _id) ???????{ ???????????SqlParameter sp = new SqlParameter(); ???????????sp.ParameterName = "@id"; ???????????sp.Value = _id; ???????????return SqlHelper.ExecuteNonQuery("UPDATE dbo.UserInfo SET ErrTimes=0 WHERE id = @id", ???????????????new SqlParameter("@id", SqlDbType.Int) { Value = _id}); ???????} ???????/// <summary> ???????/// 更新错误时间 ???????/// </summary> ???????/// <param name="_id"></param> ???????/// <returns></returns> ???????public int UpDateLastErrTime(int _id) ???????{ ???????????return SqlHelper.ExecuteNonQuery("UPDATE dbo.UserInfo SET LastErrTime = GETDATE() WHERE id = @id", ???????????????new SqlParameter("@id", SqlDbType.Int) { Value = _id}); ???????} ???????/// <summary> ???????/// 更新错误次数 ???????/// </summary> ???????/// <param name="_id"></param> ???????/// <returns></returns> ???????public int UpDateErrTimes(int _id) ???????{ ???????????return SqlHelper.ExecuteNonQuery("update UserInfo Set ErrTimes=ErrTimes+1 where id=@id", ???????????????new SqlParameter("@id", SqlDbType.Int) { Value=_id}); ???????} ???}}

using System;using System.Collections.Generic;using System.Data;using System.Linq;using System.Text;using System.Threading.Tasks;namespace FLogin.BLL{ ???class Student ???{ ???????/// <summary> ???????/// 取的学员列表 ???????/// </summary> ???????/// <returns></returns> ???????public DataTable GetStudents() ???????{ ???????????DAL.Student dal = new DAL.Student(); ???????????return dal.GetStudents(); ???????} ???}}

using System;using System.Collections.Generic;using System.Data;using System.Linq;using System.Text;using System.Threading.Tasks;namespace FLogin.BLL{ ???class UserInfo ???{ ???????/// <summary> ???????/// 判断是否登录成功！！ ???????/// </summary> ???????/// <param name="_name"></param> ???????/// <param name="_pwd"></param> ???????/// <returns></returns> ???????public bool ChechLogin(string _name, string _pwd) ???????{ ???????????DAL.UserInfo dal = new DAL.UserInfo(); ???????????DataTable dt = dal.GetUserByName(_name); ???????????// 三种情况：1.账号不存在 2.密码错误 3.登录锁定 ???????????// 这个判断只能存在一个账户。 ???????????if (dt.Rows.Count != 1) { return false; } ???????????DataRow dr = dt.Rows[0]; ???????????if (Convert.ToInt32(dr[5]) < 15) ???????????{ ???????????????return false; ???????????} ???????????if (dr[2].ToString() == _pwd) ???????????{ ???????????????dal.ReSetErrTimes(Convert.ToInt32(dr[0]));// 登录成功后，重置错误次数 ???????????????return true; ???????????} ???????????else ???????????{ ???????????????// 密码不正确 ???????????????// 更新错误次数，更新数据库，dr里面的数据是在更新之前就取出来了。 ???????????????dal.UpDateErrTimes(Convert.ToInt32(dr[0])); ???????????????// 错误三次就更新错误时间 ???????????????if (Convert.ToInt32(dr[3]) + 1 == 3) ???????????????{ ???????????????????dal.UpDateLastErrTime(Convert.ToInt32(dr[0]));//记录最后错误时间 ???????????????????dal.ReSetErrTimes(Convert.ToInt32(dr[0]));//重置错误次数 ???????????????} ???????????????return false; ???????????} ????????} ???}}

using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Windows.Forms;namespace FLogin{ ???public partial class FLogin : Form ???{ ???????public FLogin() ???????{ ???????????InitializeComponent(); ???????} ???????private void btnOK_Click(object sender, EventArgs e) ???????{ ???????????// 设置当前窗口对系那个DialogResult就会关闭窗口，并且有返回值 ???????????// 前提是这个窗口是被ShowDialog出现的 ???????????// ShowDialog的返回值就是这设置的DialogResult ???????????BLL.UserInfo bll = new BLL.UserInfo(); ???????????if (bll.ChechLogin(tbName.Text, tbPassWord.Text)) ???????????{ ???????????????this.DialogResult = DialogResult.OK; ???????????} ???????????else ???????????{ ???????????????MessageBox.Show("登录失败！！"); ???????????} ???????} ???????private void btnSorry_Click(object sender, EventArgs e) ???????{ ???????????this.DialogResult = DialogResult.Cancel; ???????} ???}}

using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Windows.Forms;namespace FLogin{ ???public partial class FMain : Form ???{ ???????public FMain() ???????{ ???????????InitializeComponent(); ???????} ???????private void 学员管理ToolStripMenuItem_Click(object sender, EventArgs e) ???????{ ???????????FStu fs = new FStu(); ???????????//设置将一个窗口显示在这个窗口内部，前提，这个窗口是一个多文档窗口(isMdiContainer=true) ???????????fs.MdiParent = this; ???????????fs.Show(); ???????} ???}}

using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Windows.Forms;namespace FLogin{ ???public partial class FStu : Form ???{ ???????public FStu() ???????{ ???????????InitializeComponent(); ???????} ???????private void FStu_Load(object sender, EventArgs e) ???????{ ???????????BLL.Student bll = new BLL.Student(); ???????????DataTable table = bll.GetStudents(); ???????????dvgMain.DataSource = table; ???????} ???}}

using System;using System.Collections.Generic;using System.Linq;using System.Threading.Tasks;using System.Windows.Forms;namespace FLogin{ ???static class Program ???{ ???????/// <summary> ???????/// 应用程序的主入口点。 ???????/// </summary> ???????[STAThread] ???????static void Main() ???????{ ???????????Application.EnableVisualStyles(); ???????????Application.SetCompatibleTextRenderingDefault(false); ???????????// 首先创建窗体对象 ???????????FLogin f1 = new FLogin(); ???????????if (f1.ShowDialog() == DialogResult.OK) ???????????{ ???????????????Application.Run(new FMain()); ???????????} ???????????????????} ???}}