Writing Excel Macros with VBA, 2nd Edition

Chapter 8. Control Statements

We conclude our discussion of the VBA language with a discussion of the main VBA control statements , which are statements that affect the flow of control (or flow of execution) in a program.

The If...Then Statement

The If...Then statement is used for conditional control. The syntax is:

If Condition Then
   ' statements go here . . .
ElseIf AnotherCondition Then
   ' more statements go here . . .
Else
   ' more statements go here . . .
End If

Note that we may include more than one

ElseIf part and that both the ElseIf part(s) and the Else part are optional. We can also squeeze all parts of this statement onto a single line, which is generally only a good idea when the ElseIf and Else parts are missing. As an example, the following code deletes the current selection in the active worksheet if it contains more than one cell:

If Selection.Count > 1 Then Selection.Delete

The following example changes the color of the current selection based upon its location—selected cells in odd-numbered rows are colored red, those in even-numbered rows are colored blue:

Dim oCell As Range
For Each oCell In Selection.Cells
  If (oCell.Row Mod 2) = 1 Then
    ' odd
    oCell.Interior.ColorIndex = 3   ' red
  Else
    ' even
    oCell.Interior.ColorIndex = 5   ' blue
  End If
Next

The For Loop

The For...Next statement provides a method for repeatedly looping through a block of code (that is, one or more lines of code). This loop is naturally referred to as a For loop. The basic syntax is:

For counter ...