Using the Print Method

Like any other VB method, you must use the dot operator syntax to call the method from its object. Because you don’t need to declare an object variable to use the Debug object, you just invoke the method from the object itself, like this:

Debug.Print "Eat at Joe’s."

If this statement were in your code, the message "Eat at Joe’s." would appear in the Immediate window when this line executed in your code. More useful messages might tell you that a particular function has been entered, or into which branch of a conditional test your code has entered. For instance:

LISTING 18.2
MORE USEFUL MESSAGES

Select Case iConditionTest
Case 1
Debug.Print "Branched into Case 1"
‘ real case 1 code follows
Case 2
Debug.Print "Branched into Case 2"
‘ real case 2 code follows
‘ Case etc.
End Select

Although you could also find out this kind of information by singlestepping through your code in Break mode and observing the path of execution, using the Immediate window to display signpost messages saves you the bother of manually stepping through the code. It is especially handy when all you wanted to know was the information displayed in the signpost itself. If you just want to know whether your code branches into condition A rather than condition B, and the details of execution are otherwise unimportant, a message in the Immediate window is much more convenient than single-stepping.

Because this is a debugging technique, you may recall a lesson from the chapter on conditional compilation that explains how to keep your debug code from inadvertently making its way into a product release. One way to prevent your Debug.Print statements from appearing in the release version of your programs might be to wrap in a conditional compiler block like this:

#CONST DebugConstant = 1
#If DebugConstant Then
Debug.Print "This message only appears when
DebugConstant is True"
#End If

Fortunately, Microsoft did everyone a favor that saves the bother of writing a conditional compiler block every time you want to use Debug.Print. Statements involving the Debug object are effectively stripped out of your program when it is compiled.

NOTE - When Debug Messages Appear: The Debug.Print message appears only when testing an application in the debugging environment. When a user runs an application, it is not running in the debugging environment, so there is no Immediate window to display the message.