dddddd/ДобавитьПол.cs

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 ЭлектронныйЖурнал
{
    public partial class ДобавитьПол : Form
    {
        SqlConnection connection;
        SqlCommand command;
        SqlDataAdapter adapter;
        DataTable table;
        string conn = "Server=DESKTOP-JES5T51\\SQLEXPRESS;DataBase=EJBD;Trusted_connection=true";
        public ДобавитьПол()
        {
            InitializeComponent();
            connection = new SqlConnection("Server=DESKTOP-JES5T51\\SQLEXPRESS;DataBase=EJBD;Trusted_connection=true");
            command = new SqlCommand();
            command.Connection = connection;
            command.CommandText = Text;
            adapter = new SqlDataAdapter(command);
            table = new DataTable();
        }
        private void ShowTable(string text)
        {
            dataGridView1.Columns.Clear();
            dataGridView1.DataSource = null;
            command.CommandText = text;
            table.Clear();
            adapter.Fill(table);
            dataGridView1.DataSource = table;
        }
        private void Пользователи_Load(object sender, EventArgs e)
        {
            ShowTable("Select Login as Логин, Password as Пароль from Пользователи");
        }

        private void AddButton_Click(object sender, EventArgs e)
        {
            {

                if (string.IsNullOrEmpty(LoginB.Text) || string.IsNullOrEmpty(PassB.Text))
                {
                    MessageBox.Show("Не все поля заполнен!");
                    return;
                }
                else
                {
                    if (MessageBox.Show("Добавить нового пользователя?", "Внимание", MessageBoxButtons.YesNo, MessageBoxIcon.Question) == DialogResult.Yes)
                    {
                        try
                        {

                            connection.Open();
                            command.CommandText = "INSERT INTO Пользователи (Login, Password) VALUES(@l,@p)";
                            command.Parameters.AddWithValue("@l", LoginB.Text);
                            command.Parameters.AddWithValue("@p", PassB.Text);
                            command.ExecuteReader();
                            command.Parameters.Clear();
                            connection.Close();


                            MessageBox.Show("Новый пользователь был добавлен!");
                            ShowTable("Select Login as Логин, Password as Пароль from Пользователи");
                        }
                        catch (Exception ex)
                        {
                            MessageBox.Show(ex.Message);
                            command.Parameters.Clear();
                            connection.Close();
                        }
                    }
                }
            }
        }

        private void DeleteButton_Click(object sender, EventArgs e)
        {
            if (MessageBox.Show("вы хотите удалить?", "Ошибка", MessageBoxButtons.YesNo, MessageBoxIcon.Question) == DialogResult.Yes)
            {
                connection.Open();
                command.CommandText = ("Delete From Пользователи Where Login=@l");
                command.Parameters.AddWithValue("@l", dataGridView1.CurrentRow.Cells[0].Value);
                command.ExecuteReader();
                command.Parameters.Clear();
                connection.Close();
                MessageBox.Show("Запись была удалена");
                ShowTable("Select Login as Логин, Password as Пароль from Пользователи");
            }
        }

        private void Back_Click(object sender, EventArgs e)
        {
            Menu i = new Menu();
            i.Show();
            this.Hide();
        }
    }
}