private void сменаПользователяToolStripMenuItem_Click(object sender, EventArgs e)
 {
     //AuthorizationForm authForm = new AuthorizationForm(this);
     form.Clear();
     form.Show();
     form = null;
     this.Close();
 }
        public MainForm(AuthorizationForm form, bool admin)
        {
            this.form = form;
            InitializeComponent();

            if (!admin)
            {
                базаДанныхToolStripMenuItem.Visible = false;
                опцииToolStripMenuItem.Visible      = false;
            }
        }