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Multiple-Document Interface (MDI) Applications

Multiple-document interface (MDI) applications enable 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.


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.

In This Section

How to: Create MDI Parent Forms

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

How to: Create MDI Child Forms

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

How to: Determine the Active MDI Child

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

How to: Send Data to the Active MDI Child

Gives directions for transporting information to the active child window.

How to: Arrange MDI Child Forms

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

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