C#

using System.Windows.Forms;

static class Program
{
    static void Main()
    {
        Application.Run(new Form1());
    }
}

class Form1 : Form
{
    public Form1()
    {
        var menuStrip1 = new MenuStrip();
        var fileToolStripMenuItem = new ToolStripMenuItem();
        menuStrip1.Items.AddRange(new ToolStripItem[] { fileToolStripMenuItem });
        for (int i = 0; i < 10; i++)
        {
            var item = new ToolStripMenuItem("Item" + i.ToString());
            fileToolStripMenuItem.DropDownItems.Add(item);
            if (i < 5)
                item.Visible = false;
        }

        fileToolStripMenuItem.Text = "File";
        Controls.Add(menuStrip1);
        MainMenuStrip = menuStrip1;
    }
}