Beginning Access™ 2007 VBA

2.4. Using Variables and Constants to Store Values

Now that you have a basic understanding of how to create procedures, turn your attention to learning how to use variables and constants in those procedures. Variables and constants can be used to store values that are used by your Access program. You have already seen a few examples of using variables to store values. This chapter covers variables in a bit more detail because they are so important to writing VBA code.

2.4.1. Types of Variables

Various types of variables can be declared and used in your procedures. The most common variables are probably String, Integer, Long, Currency, and Date, although other variables are also commonly used. The following table illustrates the various data types that are available in VBA and offers an explanation of the type of value each can store.

Figure 2.25. Figure 2-25

Data Type	What It Stores
Attachment	File attachment
Boolean	True or false
Byte	Positive integers from 0 to 255
Currency	Positive and negative currency values with four decimal places
Date	Date and time from 1/1/0100 to 12/31/9999
Double	8-byte decimal values
Hyperlink	URL for a hyperlink
Integer	2-byte integers from −32,768 to +32,768
Long	4-byte integers from −2 billion to +2 billion
Object	Access object reference
Single	4-byte decimal values

Data Type	What It Stores
String (variable length)	From 0 to 2 billion characters
String (fixed length)	From ...