Solved: Regex Query

[cosmarchy]

Hello all,

I am trying to filter through files of a specific format and have a regex query of [A-Za-z][0-9][0-9][0-9][0-9][0-9][0-9]

Unfortunately I am also picking up files with this name abc123456def but I only want c123456.

I am assuming that it is doing this because c123456 is in the middle of abc123456def...

How do I limit this to only pick up the exact regex expression?

Any help is appreciated.

Thanks

[Simon Lloyd]

Have you tried: [Cc][0-9][0-9][0-9][0-9][0-9][0-9] or [C-Cc-c][0-9][0-9][0-9][0-9][0-9][0-9]

[cosmarchy]

Have you tried: [Cc][0-9][0-9][0-9][0-9][0-9][0-9] or [C-Cc-c][0-9][0-9][0-9][0-9][0-9][0-9]

Thanks Simon but unfortunately it did not work!!

[Simon Lloyd]

Maybe its: [.C][0-9][0-9][0-9][0-9][0-9][0-9]

[Simon Lloyd]

Look here half way down!

[RichardSchollar]

Hi

$ anchors the regex at the start of the string expression being tested, so your pattern should be:

$[A-Za-z]\d{6}

Richard

[Simon Lloyd]

Richard i know nothing about regex as you can tell but could you explain why your suggestion will only pick out the C's and why {6} will find digits 0-9 (although i understand that it probably means 6 characters after the letter(s))?

[mdmackillop]

KB Item on RegExp

[RichardSchollar]

Richard i know nothing about regex as you can tell but could you explain why your suggestion will only pick out the C's and why {6} will find digits 0-9 (although i understand that it probably means 6 characters after the letter(s))?

Hi Simon

It won't just pick out the Cs - it matches a pattern at the start of the string under test that begins with an alphabet character (upper or lower case doesn't matter) followed by a string of numeric digits 6 characters long (as you rightly identified).

Hence:

A000001.xls

Z123456RichardFile.txt

Q65432199999.xls

will all result in a match, but:

123456tyu.xls

ABC123456.xls

won't as they don't meet the specified pattern.

\d is a shortcut expression for [0-9]. The {6} can be used to specify a given number of characters and, additionally a minimum number of characters:

\d{2,}

a maximum number of characters:

\d{,3}

or a specified range of characters:

\d{2,3}

(which is 'between 2 and 3 numeric characters').

Richard