Need a regular expression that will not allow a string to be "COM"

[groadsvb]

This expression will be used to validate codes that can be up to 10 characters long, but it cannot be the code of "COM" anything else is ok. I have tried a few things but not quite there. Any suggestions will be great.

 

[JohnH]

Dim pattern = "^((?!COM).){10}$"

That is a start of string, negative lookahead and match any char (grouped), repeat group 10 times, end of string. Regular-Expressions.info - Regex Tutorial, Examples and Reference

You can also just use the String class for validating such a simple pattern (String.Length and Not String.Contains).

 

[Dunfiddlin]

Is COM the whole code? COMxxxx? xxxxxCOM?

 

[groadsvb]

Is COM the whole code? COMxxxx? xxxxxCOM?

Yes that would be the entire code that is not acceptable. Any other combination of characters up to 10 in length is exceptable.

 

[JohnH]

characters up to 10 in length

In that case set repeat to range {1,10}.