Is there any limitation for IF condition while using "OR" in vb?

Question

In my code i want to use if condition. In which i want to use "OR" around 18 times. Like for e.g.

If a="something" or a="something" or a="something" or.........(up to 18 times)... then
  'do nothing
else
  'do action
end if

[Note : value of a is changing in For loop every time] so i just want to ask does there any limitation in IF for using OR in limited times. OR is there any other better way to do the same.

Thanks

Answer 1

As far as I know, there is no limitation when using OR this way.

Yet, you may consider alternative ways of coding this.

Negating a condition using Not

First, if you do nothing in the first case, then consider using the Not statement:

If Not True Then
'do somethin
'no else
End If

Consider using Select Case

Second, if you are checking the very same variable, you could either consider using a Select Case but it doesn't seem appropriate in your case if you have only one case.

Try to use a search

Eventually, if you are checking strings, you could probably better use a search within an array (with Application.Match if you are within Excel or .Contains) or within a String using Instr.

Using a collection or a dictionary

[EDIT] Another very good way to handle this would be to use the Dictionary Structure of VBA and check if a exists (see MSDN for some information).

Answer 2

This answer is just an elaboration on my comments to JMay, full credit to him. I think the original poster meant to the "Something" in his question differ, with a being the loop variable.

For each a in MyList

   Select Case a
   Case "something", "something2", "something3", "something4", "something5", _
        "something6", "something7", "something8", "something9", "something10", _
        "something11", "something12", "something13", "something14", "something15", _
        "something16", "something17", "something18"

       'DO NOTHING

   Case Else

       'do-something code goes here
       ' and here
       ' and here
       ' and here
   End Select

Next a