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Select Case vs If Then

The difference is really minimal. Practically, you wouldn't notice it I think. The difference is too small and/or can be caused by a background process... Because the code below has been called 500.000 times, and that 5 times... one major thing:It could be the "rnd" statement. But still the difference will be unnoticable

Code: Public Sub TestOne() Dim intRND As Integer intRND = CInt(Rnd * 10) If intRND = 0 Then '//Do nothing ElseIf intRND = 1 Then '//Do nothing ElseIf intRND = 2 Then '//Do nothing ElseIf intRND = 3 Then '//Do nothing ElseIf intRND = 4 Then '//Do nothing Else '//Do nothing End If End Sub Public Sub TestTwo() Dim intRND As Integer intRND = CInt(Rnd * 10) Select Case intRND Case 0 '//Do nothing Case 1 '//Do nothing Case 2 '//Do nothing Case 3 '//Do nothing Case 4 '//Do nothing Case Else '//Do nothing End Select End Sub

If...Then % faster than Select Case	If...Then (sec)	Select Case (sec)
-2,9%	0,296791	0,305656
0,7%	0,303489	0,301407
1,5%	0,308557	0,304071
-5%	0,288757	0,303990
-1,1%	0,300547	0,303737

User contributed notes:

Author: grigri (grigri at spamdetector dot co dot uk)	Date: 15:03 17/03/2004
What about if you declare intRND as a Long? I believe that in that case the compiler creates a jump table rather than a series of conditionals, which is faster. I could be wrong though.
Author: Almar ()	Date: 12:03 20/03/2004
Hmm, I might try that. Never heard something about that, but there is still a lot to learn of VB :)
Author: Gregg Morrison (Gregg dot Morrison at GMRAD dot COM)	Date: 21:08 21/08/2005
Where the SELECT CASE Statement really shines is when you have a LOT of cases. For example, consider the overhead of evaluating 64 or more separate IF-THEN-ELSEIF clauses when the TRUE clause is greater than 8. The SELECT CASE Statement really shines! I Always use SELCT CASE. Note that you can also use SELECT CASE to test a value against a dynamic Variable.