public FRM_MAIN()
        {
            InitializeComponent();
            if (frm == null)
            {
                frm = this;
            }

            this.المنتوجاتToolStripMenuItem.Enabled  = false;
            this.المستخدمونToolStripMenuItem.Enabled = false;
            this.العملاءToolStripMenuItem.Enabled    = false;
        }
 static void frm_FormClosed(object sender, FormClosedEventArgs e)
 {
     frm = null;
 }