Coding Conventions

Separators

Separators are a good measure to organize sections in a module. The main separator is a comment with 80 hashes followed by a short description of the section:

'################################################################################
'# Section

Class Module

The separation in a typical class module looks like this:

'################################################################################
'# Constants and variables

'################################################################################
'# Enum and Type

'################################################################################
'# Class

'################################################################################
'# Properties

'################################################################################
'# Methods

Code Module

A plain has less sections than a #Class Module:

'################################################################################
'# Constants and variables

'################################################################################
'# Enum and Type

'################################################################################
'# Methods

Object Module

An object module is based on an object like a form (Microsoft Access) or a worksheet (Microsoft Excel). Let's take a Microsoft Access form as example:

'################################################################################
'# Constants and variables

'################################################################################
'# Enum and Type

'################################################################################
'# Form

'################################################################################
'# Controls

'################################################################################
'# Methods

You notice the parallels to a class module, just the "Class" is here replaced by "Form" and the "Properties" are the "Controls".

Subsections

If the code should become lengthy (which it should not, but sometimes it happens), it is wise to subdivide the sections into subsections. The separator for a subsection is a lighter variant of the section separator built out of hyphens:

'--------------------------------------------------------------------------------
'- Subsection

The right choice of subsections affects the readability of code, typical use cases are the separation of

• public and private and / or
• functional domains

Applying at least one of these types of subsections should divide your code into smaller more easily maintainable parts and enhance at the same time the readability and coprehension of your code.

Organization

Organizing the code beyond the subdivision into sections also simplifies the code maintenance:

Order

If your module is for example a Microsoft Access form, you should rearrange the methods according to their (likeliness) of occurrence.

In the "Form" section this would result in the order: Open, Load, Resize, Activate, Current. Unused functions can be omitted of course.

Hierarchy

There are functions that will be called first and functions that will be called by other functions (and which are usually declared private). It is good practice to define the called functions after the calling functions.

By doing so you allow the reader of your code to first envision your intention and then to read how you solved the different tasks.

Function Names

A function name

• describes what the function does
• starts with a verb
• starts lowercase

Sub reportDifference()
    '...
End Sub

Blank lines

• Dim block
• if, select, etc

Name parameters

• Param:="Xyz"

Obsolete constructs

• Call
• Set Nothing