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60 Friday Evening

Enumerations

An enumeration is a defined data type that contains a set of symbolic constants as specified
by the programmer. When a variable is declared as an enumeration type, it can take only
these predefined values. Enumerations are useful when a variable’s data can take only cer-
tain values, such as a variable to hold the name of the month. By using an enumeration
that contains the 12 month names, you ensure that a variable of that type never can hold
erroneous data.
You use the Enum...End Enum statement to define an enumeration:
Enum EnumName
Member1
Member2
...
End Enum

Here’s an example:
Enum Flavor
Vanilla
Chocolate
Strawberry
Coffee
End Enum
Each constant in an Enum statement is assigned a numeric value. If you do not specify
the values, they are assigned in order starting with 0. In the previous example, Vanilla has
the value 0, Chocolate has the value 1, and so on. If desired, you can specify the values
explicitly:

Enum Flavors
Vanilla = 1
Chocolate = 4
Strawberry = 7
Coffee = 16
End Enum

An Enum statement must be defined at the module level, outside of any procedure
(similar to a UDT). It then becomes available as a data type that you can use in your
variable declarations:
Dim MyIceCream As Flavor
Dim MenuItems(50) As Flavor

When working with an Enum variable, VBA’s Auto List feature displays a list of the Enum
statement’s defined constants, which is a real convenience because you can simply select
from the list rather than type the data in manually.