# Include dFrameAPI in a page loaded in a DFrame

It is possible to include a page containing dFrameAPI in a DFrame, but it will only work with IE and NS6: For those 2 browsers the content of a DFrame is stored in a IFrame and each IFrame is a window object. In NS4 the content of a DFrame is a layer and independance of layers is not strong enough to load the same library twice.

You can test this first sample:

file: advanced.includePages.html

Run the example

See the source code

Inclusion of files allow to build modular applications and is a very important feature of dFrameAPI.

It pose some problems:

- How to customize a module so that its behaviour depends on the needs of this parents.

- How a module can inherit values from its parent.

The solutions to those problems use common features such as the getParentDFrame method or the mainPage keyword.

The billing sample demonstrate a 2 level inclusion.