Declaring Variables

If you have ever programmed any macros, you are probably familiar with how you define variables using the Dim keyword. For instance, you can define an integer variable with the name MyVar as follows:

Dim MyVar As Integer

This is very straightforward, and will work fine in your code. To save a few lines in your code you may be tempted to define multiple variables per line:

Dim x, y, z As Integer

In some versions of the BASIC language, this will define and initialize three variables, each as an integer. In VBA it also appears to run properly, and no error is generated. However, there is a small problem—only the last variable (z) is actually defined as an integer. You can see how this works by using the following code:

Sub DimTest()
    Dim x, y, z As Integer
    Dim sTemp As String

    sTemp = "x is type " & VarType(x) & vbCrLf
    sTemp = sTemp & "y is type " & VarType(y) & vbCrLf
    sTemp = sTemp & "z is type " & VarType(z)

    MsgBox sTemp
End Sub

When you run the macro, the message box shows that the variable type for x and y are 0, which means that the variable is a variant (the default data type for undeclared variables). Only the last message box (for z) shows a variable type of 2, meaning an integer.

The solution is to make sure that you declare your variables one per line, or using the full syntax for each variable, as in the following:

Dim x As Integer, y As Integer, z As Integer