Function

Functions are common in all programming languages. It's a named object that performs a task and returns a value.

It is similar to a subroutine in that it returns a value.

Excel has many functions for example Sum and the VBA function statement allows you to write your own.

An example of a needed function that

if I pass a number to the function I want it to return to me the letter representing the column in Excel.

Naming
What is it?
Returning a value

Real code example ColumnLetter

Passing Parameters

You can think of a function as a black box. This means you don't know how it works, but you give it data and you get an answer.

An example of a function that adds two numbers is:



Function Sum(a,b)

  Sum = a+b

End Function

to call the function you can do something like

z = Sum(7,2)

debug.print z

Lesson