 How to Use VBA Worksheet Functions in Excel 2016 - dummies

Although VBA offers a decent assortment of built-in functions, you might not always find exactly what you need. Fortunately, you can also use most of Excel’s worksheet functions in your VBA procedures. The only worksheet functions that you cannot use are those that have an equivalent VBA function. For example, you can’t use Excel’s RAND function (which generates a random number) because VBA has an equivalent function: Rnd.

VBA makes Excel’s worksheet functions available through the WorksheetFunction object, which is contained in the Application object. Here’s an example of how you can use Excel’s SUM function in a VBA statement:

Total = Application.WorksheetFunction.SUM(Range(“A1:A12”))

You can omit either the Application part or the WorksheetFunction part of the expression. In either case, VBA figures out what you’re doing. In other words, these three expressions all work exactly the same:

Total = Application.WorksheetFunction.SUM(Range(“A1:A12”))
Total = WorksheetFunction.SUM(Range(“A1:A12”))
Total = Application.SUM(Range(“A1:A12”))

My personal preference is to use the WorksheetFunction part just to make it perfectly clear that the code is using an Excel function.

Worksheet function examples

Here, you discover how to use worksheet functions in your VBA expressions.

Finding the maximum value in a range

Here’s an example that shows how to use Excel’s MAX worksheet function in a VBA procedure. This procedure displays the maximum value in column A of the active worksheet: Using a worksheet function in your VBA code.
Sub ShowMax()
Dim TheMax As Double
TheMax = WorksheetFunction.MAX(Range(“A:A”))
MsgBox TheMax
End Sub

You can use the MIN function to get the smallest value in a range. And as you might expect, you can use other worksheet functions in a similar manner. For example, you can use the LARGE function to determine the kth-largest value in a range. The following expression demonstrates this:

SecondHighest = WorksheetFunction.LARGE(Range(“A:A”),2)

Notice that the LARGE function uses two arguments. The second argument represents the kth part — 2, in this case (the second-largest value).

Calculating a mortgage payment

The next example uses the PMT worksheet function to calculate a mortgage payment. Three variables are used to store the data that’s passed to the Pmt function as arguments. A message box displays the calculated payment.

Sub PmtCalc()
Dim IntRate As Double
Dim LoanAmt As Double
Dim Periods As Long
IntRate = 0.0625 / 12
Periods = 30 * 12
LoanAmt = 150000
MsgBox WorksheetFunction.PMT(IntRate, Periods, -LoanAmt)
End Sub

As the following statement shows, you can also insert the values directly as the function arguments:

MsgBox WorksheetFunction.PMT(0.0625 /12, 360, -150000)

However, using variables to store the parameters makes the code easier to read and modify, if necessary.

Using a lookup function

The following example uses VBA’s InputBox and MsgBox functions, plus Excel’s VLOOKUP function. It prompts for a part number and then gets the price from a lookup table. Below, range A1:B13 is named PriceList. The range, named PriceList, contains prices for parts.
Sub GetPrice()
Dim PartNum As Variant
Dim Price As Double
PartNum = InputBox(“Enter the Part Number”)
Sheets(“Prices”).Activate
Price = WorksheetFunction.VLOOKUP(PartNum, Range(“PriceList”), 2, False)
MsgBox PartNum & “ costs “ & Price
End Sub

Here’s how the GetPrice procedure works:

• VBA’s InputBox function asks the user for a part number.

• The part number the user enters is assigned to the PartNum variable.

• The next statement activates the Prices worksheet, just in case it’s not already the active sheet.

• The code uses the VLOOKUP function to find the part number in the table.

• Notice that the arguments you use in this statement are the same as those you would use with the function in a worksheet formula. This statement assigns the result of the function to the Price variable.

• The code displays the price for the part via the MsgBox function.

This procedure doesn’t have any error handling, and it fails miserably if you enter a nonexistent part number. (Try it.) If this were an actual application that’s used in an actual business, you would want to add some statements that deal with errors more gracefully.

Entering worksheet functions

You can’t use the Excel Paste Function dialog box to insert a worksheet function into a VBA module. Instead, enter such functions the old-fashioned way: by hand. However, you can use the Paste Function dialog box to identify the function you want to use and find out about its arguments.

You can also take advantage of the VBE’s Auto List Members option, which displays a drop-down list of all worksheet functions. Just type Application.WorksheetFunction, followed by a period. Then you see a list of the functions you can use. If this feature isn’t working, choose the VBE’s Tools  →  Options command, click the Editor tab, and place a check next to Auto List Members. Getting a list of worksheet functions that you can use in your VBA code.

More about using worksheet functions

Newcomers to VBA often confuse VBA’s built-in functions and Excel’s workbook functions. A good rule to remember is that VBA doesn’t try to reinvent the wheel. For the most part, VBA doesn’t duplicate Excel worksheet functions.

For most worksheet functions that are unavailable as methods of the WorksheetFunction object, you can use an equivalent VBA built-in operator or function. For example, the MOD worksheet function is not available in the WorksheetFunction object because VBA has an equivalent: its built-in Mod operator.

Bottom line? If you need to use a function, first determine whether VBA has something that meets your needs. If not, check out the worksheet functions. If all else fails, you may be able to write a custom function by using VBA.