Microsoft Access 2010 Bible

Chapter 22: Integrating Access with Other Applications

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Referencing an object library means that you can use early binding to attach to objects exposed by

the library. Once the object library is referenced, the VBA code editor uses IntelliSense — particu-

larly Auto List Members and Auto Quick Info — to help you write effective code against the object

library’s contents.

For example, assume you’ve referenced the Microsoft Word libary, and the following statements

appear in a VBA procedure:

Dim WordObj As Word.Application

Set WordObj = New Word.Application

The first statement declares an object variable (WordObj) as a Word.Application object type.

Word refers to the referenced object library, and Application is one of the exposed object

classes within the library.

The second statement instantiates the object variable. As this statement executes, VBA builds an

instance of the Word.Application object in the computer’s memory; this is the application’s

proxy, discussed in the “Creating Automation References” section, earlier in this chapter. Once the

object instantiation is complete, VBA code is able to direct the Application object to perform

work on behalf of the VBA project.

This process is called early binding because the Word.Application object is explicitly declared

and instantiated. The object type is known before the application is even started. In the next sec-

tion, you’ll read about late binding, where the type of object is not known until the code actually

executes.

Caution
For this chapter, you need to make sure that several object libraries are referenced. You may not initially have
all four of the following references checked:

Microsoft DAO Object Library

Microsoft ActiveX Data Objects

Microsoft Word Object Library

Microsoft Office Object Library

If these libraries aren’t active (or, visible at the top of the list), find them in the selection list box by scrolling to
them, and verify that they’re checked in the references list.

After you reference an Automation object library, you explicitly declare object variables from the

referenced library. The VBA IntelliSense help feature displays the objects contained within the

library as you type, as shown in Figure 22.2. After you select an object and enter a period,

IntelliSense shows you the available classes within the object (see Figure 22.3).