Paul The Programmer

Sub PutAppleInBox()

MsgBox ("There are " & AppleCount(10) & " apples in the box")

End Sub

Function AppleCount(intTotal As Integer) As Integer

Dim intRepeatThisLoop As Integer

Dim intBoxOfApples As Integer

For intRepeatThisLoop = 1 To intTotal

   intBoxOfApples = intBoxOfApples + 1

Next

AppleCount = intBoxOfApples

End Function

There’s our favourite subroutine PutAppleInBox from earlier, re-written so that there is only a MsgBox in the to do list.  The MsgBox contains the messenger function “AppleCount”, which is being asked to go off and calculate the number of apples then, bring back the result.

AppleCount is the function, we pass in a variable (in this case an integer called intTotal) and the messenger function uses this variable to carry out its own to do list of instructions. Once complete the function passes back the resulting variable, in this case As an Integer.

Functions and subroutines can be as complex or simple as you want to make them. But, by splitting down a longer program into a series of subs and functions you ensure you’ve left yourself lots of bug hunting and code-re-writing for weeks years to come!