Multiple-Document Interface (MDI) Applications

Multiple-document interface (MDI) applications allow you to display multiple documents at the same time, with each document displayed in its own window. MDI applications often have a Window menu item with submenus for switching between windows or documents.

Note   There are some behavior differences between MDI forms and single-document interface (SDI) windows in Windows Forms. The Opacity property does not affect the appearance of MDI child forms. Additionally, the CenterToParent method does not affect the behavior of MDI child forms. For information on determining the position of the child windows of an MDI application, see Arranging MDI Child Forms

In This Section

Creating MDI Parent Forms

Gives directions for creating the "container" for the multiple documents within an MDI application.

Creating MDI Child Forms

Gives directions for creating one or more windows that operate within an MDI parent form.

Determining the Active MDI Child

Gives directions for verifying the child window that has focus (and sending its contents to the Clipboard).

Sending Data to the Active MDI Child

Gives directions for transporting information to the active child window.

Arranging MDI Child Forms

Gives directions for tiling, cascading, or arranging the child windows of an MDI application.

Related Sections

Creating a Window List for an MDI Form

Gives directions for showing a list of the windows currently open in an application.

Windows Forms Layout Options

Provides information about form layout styles.

What's New in Windows Forms and Controls

Describes the new features of Windows Forms and controls.