How to: Remove a ToolStripMenuItem from an MDI Drop-Down Menu (Windows Forms)

In some applications, the kind of a multiple-document interface (MDI) child window can be different from the MDI parent window. For example, the MDI parent might be a spreadsheet, and the MDI child might be a chart. In that case, you want to update the contents of the MDI parent's menu with the contents of the MDI child's menu as MDI child windows of different kinds are activated.

The following procedure uses the IsMdiContainer, AllowMerge, MergeAction, and MergeIndex properties to remove a menu item from the drop-down part of the MDI parent menu. Closing the MDI child window restores the removed menu items to the MDI parent menu.

1. Create a form and set its IsMdiContainer property to true.

2. Add a MenuStrip to Form1 and set the AllowMerge property of the MenuStrip to true.

3. Add a top-level menu item to the Form1MenuStrip and set its Text property to &File.

4. Add three submenu items to the &File menu item and set their Text properties to &Open, &Import from, and E&xit.

5. Add two submenu items to the &Import from submenu item and set their Text properties to &Word and &Excel.

6. Add a form to the project, add a MenuStrip to the form, and set the AllowMerge property of the Form2MenuStrip to true.

7. Add a top-level menu item to the Form2MenuStrip and set its Text property to &File.

8. Add an &Import from submenu item to the &File menu of Form2, and add an &Word submenu item to the &File menu.

9. Set the MergeAction and MergeIndex properties of the Form2 menu items as shown in the following table.

   Expand table

   Form2 menu item	MergeAction value	MergeIndex value
   File	MatchOnly	-1
   Import from	MatchOnly	-1
   Word	Remove	-1

10. In Form1, create an event handler for the Click event of the &OpenToolStripMenuItem.

11. Within the event handler, insert code similar to the following code example to create and display new instances of Form2 as MDI children of Form1:

    Private Sub openToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles openToolStripMenuItem.Click
        Dim NewMDIChild As New Form2()
        'Set the parent form of the child window.
            NewMDIChild.MdiParent = Me
        'Display the new form.
            NewMDIChild.Show()
    End Sub
    

    private void openToolStripMenuItem_Click(object sender, EventArgs e)
    {
        Form2 newMDIChild = new Form2();
        // Set the parent form of the child window.
            newMDIChild.MdiParent = this;
        // Display the new form.
            newMDIChild.Show();
    }
    

12. Place code similar to the following code example in the &OpenToolStripMenuItem to register the event handler.

    Private Sub openToolStripMenuItem_Click(sender As Object, e As _
    EventArgs) Handles openToolStripMenuItem.Click
    

    this.openToolStripMenuItem.Click += new _
    System.EventHandler(this.openToolStripMenuItem_Click);
    

This example requires:

• Two Form controls named Form1 and Form2.

• A MenuStrip control on Form1 named menuStrip1, and a MenuStrip control on Form2 named menuStrip2.

• References to the System and System.Windows.Forms assemblies.

• How to: Create MDI Parent Forms
• How to: Create MDI Child Forms
• MenuStrip Control Overview