How to get the contextmenustrip of deeply childed toolstripmenuitem

Question

Tried GetCurrentParent() and failed and read all other answers.

I am working on a project where user may click on button and generate new controls, so I have to generate them on run time.

When I created a contextmenustrip and added the following items

----------------------
  Show
----------------------
  Style -> change Color
----------------------

Both items should access richtextbox. The show click works properly but "change color" does not.

The problem occurs when I try to get the richtextbox in where the menu popped from.Show successfully access the richtextbox but changecolor does not.

Here is my code

 public static System.Windows.Forms.RichTextBox Create_rich_text_box()
  {
      System.Windows.Forms.RichTextBox r = new System.Windows.Forms.RichTextBox();
      r.ContextMenuStrip = Create_new_context_menu_strip();
      return r;
  }

  private static System.Windows.Forms.ContextMenuStrip Create_new_context_menu_strip()
  {
      //contextmenu
      System.Windows.Forms.ContextMenuStrip ctx = new System.Windows.Forms.ContextMenuStrip();

      //display contents
      var show = new System.Windows.Forms.ToolStripMenuItem("show");
      show.Click += _show_click;

      //change color
      var style = new System.Windows.Forms.ToolStripMenuItem("Style");
      var changecolor = new System.Windows.Forms.ToolStripMenuItem("change color"); 
      changecolor.Click += _chnge_color_click;
      style.DropDownItems.Add(changecolor);

      ctx.Items.Add(show);
      ctx.Items.Add(style);
      ctx.Items.AddRange(new System.Windows.Forms.ToolStripItem[] {
            });
      return ctx;
  }
  private static System.Windows.Forms.RichTextBox get_current_rtx(object sender)
  {
      try
      {
          System.Windows.Forms.ToolStripMenuItem tsm = sender as System.Windows.Forms.ToolStripMenuItem;
          var par = tsm.GetCurrentParent();
          var ctx = (par as System.Windows.Forms.ContextMenuStrip);
          return ctx.SourceControl as System.Windows.Forms.RichTextBox;
      }
      catch { }
      return null;

  }
  private static void _chnge_color_click(object sender, EventArgs e)
  {
      System.Windows.Forms.RichTextBox r = get_current_rtx(sender);
      r.BackColor = System.Drawing.Color.Gray;
      System.Windows.Forms.MessageBox.Show("Success");

  }
  private static void _show_click(object sender, EventArgs e)
  {
      try
      {
          System.Windows.Forms.RichTextBox r = get_current_rtx(sender);
          System.Windows.Forms.MessageBox.Show(r.Text);
      }
      catch
      {
          System.Windows.Forms.MessageBox.Show("This will fail");
      }
  }