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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;

using System.Data.SqlClient;

 

namespace WindowsFormsApplication1

{

    public partial class Form1 : Form

    {

        public Form1()

        {

            InitializeComponent();

        }

 

        private void Form1_Load(object sender, EventArgs e)

        {

 

        }

 

        private void btnEsc_Click(object sender, EventArgs e)

        {

            // Application.Exit();直接结束整个应用程序

            this.Close();//只关闭当前窗口，不关闭应用程序

        }

 

        private void btnLogin_Click(object sender, EventArgs e)

        {

            string name = txtName.Text.Trim();

            string pwd = txtPwd.Text;

            string connectionString = "server=.;database=Test;integrated security=true";

            using (SqlConnection connection = new SqlConnection(connectionString))

            {

                connection.Open();

                string sql = "select count(1) from Tbstudent where stuName='{0}' and stuNumber='{1}'";

                sql = String.Format(sql, name, pwd);

                using (SqlCommand cmd = new SqlCommand(sql,connection))

                {

                    int count = Convert.ToInt32(cmd.ExecuteScalar());

                    if(count>0)

                    {

                        MessageBox.Show("登陆成功");

                    }

                    else

                    {

                        MessageBox.Show("登录失败");

                    }

                }

            }

        }

    }

}