Understanding Regex

[Papa_Don]

Group,

I need to insert an "If/Then" statement that will require the command to check the string for multiple variables. In other words it needs to say something like this:

If Microsoft.VisualBasic.Mid(txtLine, 18, 1) = "C" or "T" or "G" or "W" Then
    Go do something
End If

After doing some reading, it seems that "Regex" may be the way to correctly write this. However this is a new command to me and I'm not sure how to write something like this. Can you give me a hand?

In advance, thanks for the help.

Don

[Minimalist]

Looks more like a select case statement where there are more than one clause. See a good example of it here:
https://msdn.microsoft.com/de-de/library/cy37t14y.aspx

[Papa_Don]

Minimalist, You're probably on the right track for me. However I'm not sure I understand "Select Case" even after reading as I'm not sure how to incorporate this in my If/Then statement. This is because my statement is going to be somewhat complex.

I think I will mark this solved and resubmit the question as "If/Then and Select Case".

[Reverend Jim]

There is an addin tool available for versions of Visual Studio up to 2012 that will allow you to easily test your regular expressions. You can find it here