How to: Append a MenuStrip to an MDI Parent Window (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 append the MDI child menu to the MDI parent menu. Closing the MDI child window removes the appended menu from the MDI parent.

For more information, see Multiple-Document Interface (MDI) Applications and Multiple-Document Interface (MDI) Applications and Multiple-Document Interface (MDI) Applications and Multiple-Document Interface (MDI) Applications.

To append a menu item to an MDI parent

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. Set the Visible property of the Form1 MenuStrip to false.

4. Add a top-level menu item to the Form1 MenuStrip and set its Text property to &File.

5. Add a submenu item to the &File menu item and set its Text property to &Open.

6. Add a form to the project, add a MenuStrip to the form, and set the AllowMerge property of the Form2 MenuStrip to true.

7. Add a top-level menu item to the Form2 MenuStrip and set its Text property to &Special.

8. Add two submenu items to the &Special menu item and set their Text properties to Command&1 and Command&2, respectively.

9. Set the MergeAction property of the &Special, Command&1, and Command&2 menu items to Append.

10. Create an event handler for the Click event of the &New ToolStripMenuItem.

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
    

    [C#]

    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 &Open ToolStripMenuItem 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);
    

Compiling the Code

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.