The Enum Statement | VBA Declaration Statements

by Sola Bode
in VBA Coding Constructs
March 4, 2021

The Enum statement declares VBA enumerations or Enums. Enums are widely used in VBA programs, so it's useful exploring their declaration, as you'll do here.

3 minutes read

Introducing the Enum Statement

The Enum statement declares enumerations or enums. An Enum declaration is a block that starts with an Enum statement and ends with an End Enum statement. The block contains one or more named constants, or assignments of values or expressions (of Long data type) to constants. The header image above shows the Enum statement’s syntax.

Salient Points on Its Usage

There are several vital things to note about the Enum statement:

Enums are strictly module-level identifiers (see image below). So, the Enum statement is only valid when written outside all the procedures in a module
You can include either the Private or Public keyword in the Enum statement, but not both. Regardless of your choice, you must always include the Enum keyword.
Enums have public scope by default, unlike constants which are private by default. So, the Enum and Public keywords produce the same effect. However, including the Public keyword improves code readability.
You can omit an Enum member’s (i.e., any constName in the syntax above) value assignment. In that case, the compiler assigns a number (of Long data type) to the member. Also, the compiler assigns zero (0) to the member if the member is the first in the Enum. Otherwise, the compiler assigns a number greater than the preceding Enum member’s value by one (1).
Once you’ve declared an Enum, you can declare other program identifiers with the Enum’s name as their type. These other identifiers that this applies to include variables, arguments, or function returns. Now, these variables, arguments, or function returns can only contain the values mapped to them in the Enum’s declaration.

The image below shows the different scope levels in VBA. Also, we’ve delved into scope levels in a separate article, make sure to check it out if you need a refresher.

VBA Program Identifiers – Scope Levels [from the narrowest (block level) to broadest (application level)] — VBA Program Identifier Scope Levels – from the narrowest (block-level) to broadest (application level)

Sample Code (Examples)

The sample code below shows the Enum statement in use. Also, it illustrates the salient points discussed above.

Option Explicit

'declare enums accessible only to procedures in the current module
Private Enum enu_NamesCategory
    African         'assigned a default value of '0'
    English         'assigned a default value of '1'
    Chinese = 10    'other members are given values starting from '1'
    Indian          'assigned a default value of '11'
End Enum

'declare enums accessible to procedures in/out-side the current module
Public Enum enu_SelectionCriteria
    Education = 0
    Experience = 1
    Certification = 2
End Enum
'   adding PUBLIC is more readable than using just ENUM

Sub Enum_Statement_Procedure_Level_Examples()
    
    'declare a procedure-level variable with Enum type
    Dim lng_NamesOrigin As enu_NamesCategory
    
    'see enum members' values in the Immediate Window
    'African
        lng_NamesOrigin = African
        Debug.Print "African's value is " + Str(lng_NamesOrigin)
    'English
        lng_NamesOrigin = English
        Debug.Print "English's value is " + Str(lng_NamesOrigin)
    'Indian
        lng_NamesOrigin = Indian
        Debug.Print "Indian's value is " + Str(lng_NamesOrigin)
    
    'declare a procedure-level variable with Enum type
    Dim lng_SuccessPredictor As enu_SelectionCriteria
    '   variable can only hold values assigned in enum declaration      
            
End Sub

Option Explicit

'declare enums accessible only to procedures in the current module

Private Enum enu_NamesCategory

African 'assigned a default value of '0'

English 'assigned a default value of '1'

Chinese = 10 'other members are given values starting from '1'

Indian 'assigned a default value of '11'

End Enum

'declare enums accessible to procedures in/out-side the current module

Public Enum enu_SelectionCriteria

Education = 0

Experience = 1

Certification = 2

End Enum

' adding PUBLIC is more readable than using just ENUM

Sub Enum_Statement_Procedure_Level_Examples()

'declare a procedure-level variable with Enum type

Dim lng_NamesOrigin As enu_NamesCategory

'see enum members' values in the Immediate Window

'African

lng_NamesOrigin = African

Debug.Print "African's value is " + Str(lng_NamesOrigin)

'English

lng_NamesOrigin = English

Debug.Print "English's value is " + Str(lng_NamesOrigin)

'Indian

lng_NamesOrigin = Indian

Debug.Print "Indian's value is " + Str(lng_NamesOrigin)

'declare a procedure-level variable with Enum type

Dim lng_SuccessPredictor As enu_SelectionCriteria

' variable can only hold values assigned in enum declaration

End Sub

When you run the sample code above, the Str function (lines #27, #30, and #33) returns the String representation of the Enum (which is of Long data type) passed to it as an argument. Those function return-values are displayed in the Immediate window using the Print method of the Debug object, as shown below.