`preg_match` the Whole String in PHP

Question

This thing really confuses me, pardon my ignorance.

I have a var $name in here that I want to be free from number, I don\'t want any digit to be included in

Answer 1

#3 matches because you have both letters and numbers. Your regex in English basically says

it matches if there is a non-digit character

If you want to match only non-digit characters, you have to have the regex match against the entire string and allow for an arbitrary number of characters:

^[^\d]+$

Answer 2

Try this:

<?php
    $string = "as232dda";
    $new_string = trim(str_replace(range(0,9),'',$string));
    echo $new_string;// gives 'asdda'
?>

Or function form:

<?php
  function remove_numbers($string){
    return(trim(str_replace(range(0,9),'',$string)));
  }

  $string = "as232dda";
  echo remove_numbers($string); // gives 'asdda'
?>

Answer 3

Your regex only checks that there is at least one non-digit. Instead, you need to check that it is only non-digits:

var_dump(preg_match('/^\D+$/',$name));

(^ and $ are the beginning and end of the string. \D means anything not a digit--the opposite of \d. So this only matches non-digits from beginning to end. It doesn't match an empty string. Replace + with * if you want to match an empty string as well).