private void ButtonEditUser_Click(object sender, EventArgs e)
        {
            User objt = new User
            {
                ID       = int.Parse(dataGridView1.Rows[dataGridView1.CurrentCell.RowIndex].Cells[0].Value.ToString()),
                Name     = dataGridView1.Rows[dataGridView1.CurrentCell.RowIndex].Cells[1].Value.ToString(),
                Surname  = dataGridView1.Rows[dataGridView1.CurrentCell.RowIndex].Cells[2].Value.ToString(),
                Address  = dataGridView1.Rows[dataGridView1.CurrentCell.RowIndex].Cells[3].Value.ToString(),
                Function = dataGridView1.Rows[dataGridView1.CurrentCell.RowIndex].Cells[4].Value.ToString(),
                Login    = dataGridView1.Rows[dataGridView1.CurrentCell.RowIndex].Cells[5].Value.ToString(),
                Password = dataGridView1.Rows[dataGridView1.CurrentCell.RowIndex].Cells[6].Value.ToString()
            };

            if (objt != null)
            {
                using (EditAddUserPanel frm = new EditAddUserPanel()
                {
                    UserInfo = objt
                })
                {
                    if (frm.ShowDialog() == DialogResult.OK)
                    {
                        int userId = int.Parse(dataGridView1.Rows[dataGridView1.CurrentCell.RowIndex].Cells[0].Value.ToString());
                        var user   = listOfUser.FirstOrDefault(u => u.ID == userId);
                        listOfUser.Remove(user);
                        listOfUser.Add(frm.UserInfo);
                        SortListOfUser();
                        RefreshDataGridView();
                    }
                }
            }
        }
 private void ButtonAddUser_Click(object sender, EventArgs e)
 {
     using (EditAddUserPanel frm = new EditAddUserPanel()
     {
         UserInfo = new User()
     })
     {
         if (frm.ShowDialog() == DialogResult.OK)
         {
             listOfUser.Add(frm.UserInfo);
         }
     }
     SortListOfUser();
     RefreshDataGridView();
 }