Microsoft Office Tutorials and References
In Depth Information
Chapter 5. Variables, Data Types, and Constants
Chapter 5. Variables, Data Types, and Constants
In the next few chapters, we will discuss the basics of the VBA programming language, which
underlies all of the Microsoft Office programming environments. During our discussion, we will
consider many short coding examples. I hope that you will take the time to key in some of these
examples and experiment with them.
5.1 Comments
We have already discussed the fact that comments are important. Any text that follows an
apostrophe is considered a comment and is ignored by Excel. For example, the first line in the
following code is a comment, as is everything following the apostrophe on the third line:
' Declare a string variable
Dim WksName as String
WksName = Activesheet.Name ' Get name of active sheet
When debugging code, it is often useful to temporarily comment out lines of code so they will not
execute. The lines can subsequently be uncommented to restore them to active duty. The
CommentBlock and UncommentBlock buttons, which can be found on the Edit toolbar, will place
or remove comment marks from each currently selected line of code and are very useful for
commenting out several lines of code in one step. (Unfortunately, there are no keyboard shortcuts
for these commands, but they can be added to a menu and given menu accelerator keys.)
5.2 Line Continuation
The very nature of Excel VBA syntax often leads to long lines of code, which can be difficult to
read, especially if we need to scroll horizontally to see the entire line. For this reason, Microsoft
recently introduced a line-continuation character into VBA. This character is the underscore,
which must be preceded by a space and cannot be followed by any other characters (including
comments). For example, the following code:
ActiveSheet.Range("A1").Font.Bold = _
True
is treated as one line by Excel. It is important to note that a line continuation character cannot be
inserted in the middle of a literal string constant, which is enclosed in quotation marks.
5.3 Constants
The VBA language has two types of constants. A literal constant (also called a constant or literal )
is a specific value, such as a number, date, or text string, that does not change, and that is used
exactly as written. Note that string constants are enclosed in double quotation marks, as in
"Donna Smith" and date constants are enclosed between number signs, as in #1/1/96# .
For instance, the following code stores a date in the variable called dt :
 
 
 
 
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