private void tbRegMail_KeyUp(object sender, KeyEventArgs e)
        {
            if (e.Key == Key.Enter)
            {
                if (tbRegLogin.Text == "" || tbRegPass.Password == "" || tbRegMail.Text == "" || IsValidEmail(tbRegMail.Text) == false || (tbRegLogin.Text.IndexOf(' ') >= 0) || (tbRegPass.Password.IndexOf(' ') >= 0))
                {
                    /*ToolTip toolTip = new ToolTip();
                     * StackPanel toolTipPanel = new StackPanel();
                     * toolTipPanel.Children.Add(new TextBlock { Text = "Введите корректные данные", FontSize = 16 });
                     * toolTip.Content = toolTipPanel;
                     * btnReg.ToolTip = toolTip;*/
                    return;
                }


                eng._regUserKek(tbRegLogin.Text, tbRegPass.Password, tbRegMail.Text);
                //Tab1.SelectedIndex = 0;
                ttab.SelectedIndex = 0;
                tbRegLogin.Clear();
                tbRegPass.Clear();
                tbRegMail.Clear();
            }
        }