private void OpenToolStripMenuItem_Click(object sender, EventArgs e)
        {
            CreateToolStripMenuItem_Click(sender, e);
            OpenFileDialog dialog = new OpenFileDialog();

            if (dialog.ShowDialog() == DialogResult.OK)
            {
                string          sessionText = File.ReadAllText(dialog.FileName);
                LyaMelikTabPage currentPage = (LyaMelikTabPage)tabControl1.SelectedTab;
                currentPage.InputRichTextBox.Text = sessionText;
            }
        }
        private void CreateToolStripMenuItem_Click(object sender, EventArgs e)
        {
            TabNumber++;
            LyaMelikTabPage   newTabPage = null;
            ToolStripMenuItem menuItem   = sender as ToolStripMenuItem;

            if (graphToolStripMenuItem.DropDownItems.Contains(menuItem))
            {
                string title = "Graph Session" + TabNumber;
                newTabPage = new GraphLyaMelikTabPage(title);
            }
            else if (polynomialToolStripMenuItem.DropDownItems.Contains(menuItem))
            {
                string title = "Polynomial Session " + TabNumber;
                newTabPage = new PolynomialLyaMelikTabPage(title);
            }
            tabControl1.TabPages.Add(newTabPage);
            tabControl1.SelectTab(newTabPage);
        }
        private void SaveToolStripMenuItem_Click(object sender, EventArgs e)
        {
            LyaMelikTabPage currentPage = (LyaMelikTabPage)tabControl1.SelectedTab;

            currentPage.Session.SaveSession();
        }