PerevozkiBD/Perevozki/Auth.cs

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 System.Data.SqlClient;

namespace Perevozki
{
    public partial class Auth : Form
    {
        public Auth()
        {
            InitializeComponent();
            StartPosition = FormStartPosition.CenterScreen;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            DB dataBase = new DB();
            var log = textBox1.Text;
            var pass = textBox2.Text;
            SqlDataAdapter adapter = new SqlDataAdapter();
            DataTable table = new DataTable();
            string querystring = $"select Login, Password from Polzovateli where Login='{log}' and Password='{pass}'";
            SqlCommand command = new SqlCommand(querystring, dataBase.GetConnection());
            adapter.SelectCommand = command;
            adapter.Fill(table);
            if (table.Rows.Count > 0)
            {
                MessageBox.Show("Вы успешно вошли!");
                Menu f2 = new Menu();
                f2.ShowDialog();
                
            }
            else
            {
                MessageBox.Show("Неверный логин или пароль, повторите попытку");




            }
        }

    }
}