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Chapter 7: Essential VBA Language Elements
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VBA has a variety of built-in data types. Table 7-1 lists the most common
types of data that VBA can handle.
Table 7-1
VBA’s Built-In Data Types
Data Type Bytes Used Range of Values
Boolean 2 True or False
Integer 2 –32,768 to 32,767
Long 4 –2,147,483,648 to 2,147,483,647
Single 4 –3.402823E38 to 1.401298E45
Double (negative) 8 –1.79769313486232E308 to
–4.94065645841247E-324
Double (positive) 8 4.94065645841247E–324 to
1.79769313486232E308
Currency 8 –922,337,203,685,477.5808 to
922,337,203,685,477.5807
Date 8 1/1/100 to 12/31/9999
String 1 per char Varies
Object 4 Any defined object
Variant Varies Any data type
User defined Varies Varies
In general, choose the data type that uses the smallest number of bytes but
can still handle all the data you want to store in the variable.
Loop counters are often declared as integers. If you use the counter in order
to loop through rows in the worksheet, your program might just error out!
Why? Integers cannot be larger than 32,767. Beginning with Excel 2007, worksheets
have many more rows (1,048,576 to be exact). Instead, declare such
loop counters as Long.
Declaring and scoping variables
If you read the previous sections, you now know a bit about variables and
data types. In this section, you discover how to declare a variable as a certain
data type.
If you don’t declare the data type for a variable you use in a VBA routine, VBA
uses the default data type: Variant. Data stored as a variant acts like a chameleon;
it changes type depending on what you do with it. For example, if a variable
is a Variant data type and contains a text string that looks like a number