c# forms mainmenu

I have a winform that I have a main menu going horizontally across as such:

      MenuItem opt1 = new MenuItem();
      opt1.Text = "Save Image";
      opt1.Click += new EventHandler(opt1_Click);

      MenuItem opt2 = new Menu开发者_运维技巧Item();
      opt2.Text = "Upload Data";
      opt2.Click += new EventHandler(opt2_Click);

      mainMenu.MenuItems.Add(opt1);
      mainMenu.MenuItems.Add(opt2);
      form.Menu = mainMenu;

What I want is when the user clicks on 'Upload Data' a drop down menu to show, with a small number of other options. Could somebody please point me in the right direction as to what I should be looking at?

Thanks.

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Just add menu items to the opt2

opt2.MenuItems.Add(....)

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Add some items to opt2.MenuItems to create a submenu.

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I would use the Windows Forms designer. If you can't, use it to click together a dummy form with the required menu and then look in the code that was generated, copy that one.