PHP RegEx: Meta Character class

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We already seen the caret(^) as match the the beginning of string and (\z) match at the end of string that what they do.
Now we are going to look with the others with beggining of bracket []. These Meta character are specifying a character class.

What does the character class? This is a set of character that you want to match the string. They can listed individually like
[abcdf] or a range [a-f]. That is the same action.

See the sample below.

  1. <?php
  2. // create a string
  3. $string = 'ron';
  4. // Search for a match
  5. echo preg_match("/r[aoiu]n/", $string, $matches);
  6. ?>

The above code will generate 1. Because "o" will match to the preg_match("/r[aoiu]n/", $string, $matches). And this would match also "rin", "run" and "ran" but not "ren" because "e" is not belong to our condition [aoiu]. You can use also in-sensitive case by adding "i" "/r[aoiu]n/i" or you can use [AOIU] that accepts uppercase.

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