CODEWITHSUNDEEP
regex
Kicker
Kicker

Reputation: 606

Regular Expression for filename

how can I make a RegEx for remove everything from last underscore to .jpg extension in filenames?

E.g. I have 

aosta_8b08e16ae42367d29cbf11bcf27f376a.jpg
aosta_madreperla_014cb17607a4fb23fcb94a8f26efb267.jpg

and need to change it to this

aosta.jpg
aosta_madreperla.jpg

Thank you

Upvotes: 0

Views: 70

Answers (6)

Braj
Braj

Reputation: 46841

Remove the matched ones or replaced with empty string

_[^_]*(?=\.)

Online demo

Pattern explanation:

  _                        '_'

  [^_]*                    any character except: '_' (0 or more times)
  (?=                      look ahead to see if there is:
    \.                       '.'
  )                        end of look-ahead

Read more about Lookahead and Lookbehind Zero-Length Assertions that do not consume characters in the string, but only assert whether a match is possible or not.

Upvotes: 3

pavel
pavel

Reputation: 27082

You don´t need to use regexp, use just substr and strpos, it should be faster.

$str = array(
    'aosta_8b08e16ae42367d29cbf11bcf27f376a.jpg',       
    'aosta_madreperla_014cb17607a4fb23fcb94a8f26efb267.jpg'
);

foreach ($str as $s) {
    echo substr($s, 0, strrpos($s, '_')) . substr($s, -4);
    echo '<br>';
}

Upvotes: 0

vks
vks

Reputation: 67968

_(?!.*?_).*?(?=\.)

Try this.Replace by ``.See demo.

http://regex101.com/r/hQ1rP0/18

_ matches the character _ literally

(?!.*?_) Negative Lookahead - Assert that it is impossible to match the a string containing _.

(?=\.) Positive Lookahead - Assert that the string ends when it has a . ahead of it.

Upvotes: 0

Kamehameha
Kamehameha

Reputation: 5473

Try this - 

Search - ^(\w+)\_[^.]+(.*)$
Replace- \1\2

DEMO

Upvotes: 0

Amit Joki
Amit Joki

Reputation: 59232

You can just do this using this regex

/[^_]+.jpg$/

and replace with .jpg

Upvotes: 0

Avinash Raj
Avinash Raj

Reputation: 174696

Regex:

^(.*)_[^.]*

Replacement string:

$1

DEMO

Explanation:

  • ^(.*)_ Captures all characters from the start upto the last _ symbol(excluding underscore) and store it into group 1.
  • [^.]* Matches any character but not of dot zero or more times.
  • Finally all the matched characters are replaced by the chars inside group index 1.

Upvotes: 0

Related Questions