ADO.Net中的类型化DataSet登录

1.新建 DL.mdf

2.Program.cs中加入“神奇代码”

3.添加数据集 DataSetUsers.xsd

FillByUserName.....的sql语句 SELECT Id, Name, Password, ErrorTimes FROM dbo.T_Users
where Name=@Name

IncErrorTimesByID的sql语句 UPDATE [dbo].[T_Users] SET ErrorTimes=ErrorTimes+1  WHERE (Id = @Id)

ResetErrorTimes的sql语句  UPDATE [dbo].[T_Users] SET ErrorTimes=0 WHERE (Id = @Id)

4.在form1上拖两个textbox name为txtUserName  txtPassword 拖一个 button

5.Form1.cs 代码

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using 强类型登录.DataSetUsersTableAdapters;

namespace 强类型登录
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            T_UsersTableAdapter adapter = new T_UsersTableAdapter();
            强类型登录.DataSetUsers.T_UsersDataTable users = adapter.GetDataByUserName(txtUserName.Text);
            if (users.Count <= 0)
            {
                MessageBox.Show("用户名错误 ");
            }
            else
            {
                强类型登录.DataSetUsers.T_UsersRow user = users[0];
                if (user.ErrorTimes > 3)
                 {
                 MessageBox.Show("错误次数过多");
                 return;
                 }
                if (user.Password == txtPassword.Text)
                {
                    MessageBox.Show("登录成功");
                    adapter.ResetErrorTimes(user.Id);
                }
                else
                {
                    adapter.IncErrorTimesByID(user.Id );
                    MessageBox.Show("密码错误");
                }

            }
        }
    }
}

6.运行结果

 7.代码https://files.cnblogs.com/hao1234/%E5%BC%BA%E7%B1%BB%E5%9E%8B%E7%99%BB%E5%BD%95.rar

   感谢杨中科老师的视频 第五季