Word Document Properties

Part II: Learning the Ropes 
10_046500 ch05.qxp 12/5/06 5:35 PM Page 116

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You might find it confusing to continually convert between column letters
and numbers when working with large worksheets. To avoid this problem,
you can define global constants with the numbers. A 
Column_A
constant
would equal 
1
and so on. Using this technique can make your code easier to
read when you use large worksheets.
The first 
If...Then
statement checks whether the first number is greater than
or equal to the second. You might wonder why the code doesn’t simply check
for equality. Using this technique reduces the amount of code that you have to
write. Notice that the second 
If...Then
statement immediately chooses
between equality and greater than. It relies on a nested 
If...Then...Else
structure to choose between two values for the 
Output
string. This is a good
example of how to use nesting within your programs.
If the first 
If...Then
statement is false, the 
Else
statement immediately exe-
cutes. Notice how the use of nesting saves VBA two checks. When you use indi-
vidual 
If...Then
statements, VBA must make three decisions every time that
it compares the two numbers. Using the nested 
If...Then...Else
structure
shown in the code reduces the number of decisions to one.
The final line of code outputs the comparison results to the worksheet. Try
various numbers, and you can see how the nested decision technique works.
Using the If...Then...ElseIf statement
When making multiple comparisons, you can use the 
If...Then...ElseIf
statement to make the code easier to read. Using this format can also reduce
the number of decisions that VBA must make, which ensures that your code
runs as quickly as possible. Listing 5-3 shows an alternative form of the exam-
ple in the preceding “Using the If...Then...Else statement” section. (You can
find the source code for this example on the Dummies.com site at
http://www.dummies.com/go/vbafd5e
.)