Question

I am trying to make a regular expression but i am newbie in it. And it seems Like i am failing again and again in this..

Kindly if anyone can help me

Basically what i want an expression that tests for the following,

1- Something that starts with abc or def, followed by a number between
0 and 900, then can have anything between that, up until the nearest
!!

Any help will be regarded

Best Regards

Answer 1

If you want this abcXXX(0<xxx<900) or defXXX (0<xxx<900) try this:

\b(abc)([0-9]|[1-9][0-9]|[1-8][0-9][0-9]|900)\b|\b(def)([0-9]|[1-9][0-9]|[1-8][0-9[0-9]|900)\b]

Explanation: The regex [0-9] matches single-digit numbers 0 to 9. [1-9][0-9] matches double-digit numbers 10 to 99. That’s the easy part. So 0-900 is 0-899 and 900 so REGEX is [0-9]|[1-9][0-9]|[1-8][0-9][0-9]|900 . Add \b( )\b is Boundary Matchers. Similar to def : start with def followed by 3 digits.

\b(def)([0-9]|[1-9][0-9]|[1-8][0-9][0-9]|900)\b

At last use | is or.

Tested with Regular Expression Test Page for Java

Maybe i didn’t try some weird input but this is the basic parts for you to dig by yourself

Edit with Alan Moore’s nicer suggestion :

\b(abc|def)([0-9]|[1-9][0-9]|[1-8][0-9][0-9]|900)\b