How to separate letters and digits from a string in php

Question

I have a string which is combination of letters and digits. For my application i have to separate a string with letters and digits: ex:If my string is "12jan" i hav to get "12" "jan" separately..

Answer 1

$numbers = preg_replace('/[^0-9]/', '', $str);
$letters = preg_replace('/[^a-zA-Z]/', '', $str);

Answer 2

You can make use of preg_split to split your string at the point which is preceded by digit and is followed by letters as:

$arr = preg_split('/(?<=[0-9])(?=[a-z]+)/i',$str);

Code in Action

<?php
$str = '12jan';
$arr = preg_split('/(?<=[0-9])(?=[a-z]+)/i',$str);                                                               
print_r($arr);

Result:

Array
(
    [0] => 12
    [1] => jan
)

Answer 3

preg_match_all('/^(\d+)(\w+)$/', $str, $matches);

var_dump($matches);

$day = $matches[1][0];
$month = $matches[2][0];

Of course, this only works when your strings are exactly as described "abc123" (with no whitespace appended or prepended).

If you want to get all numbers and characters, you can do it with one regex.

preg_match_all('/(\d)|(\w)/', $str, $matches);

$numbers = implode($matches[1]);
$letters = implode($matches[2]);

var_dump($numbers, $letters);

See it!

Answer 4

$string = "12312313sdfsdf24234";
preg_match_all('/([0-9]+|[a-zA-Z]+)/',$string,$matches);
print_r($matches);

this might work alot better

Answer 5

This works for me as per my requirement, you can edit as per yours

function stringSeperator($string,$type_return){

    $numbers =array();
    $alpha = array();
    $array = str_split($string);
    for($x = 0; $x< count($array); $x++){
        if(is_numeric($array[$x]))
            array_push($numbers,$array[$x]);
        else
            array_push($alpha,$array[$x]);
    }// end for         

    $alpha = implode($alpha);
    $numbers = implode($numbers);

    if($type_return == 'number')    
    return $numbers;
    elseif($type_return == 'alpha')
    return $alpha;

}// end function

Answer 6

You can split the string by matching sequences of digits or non-digits, then "forgetting" the matched characters with \K.

preg_split(
    '~(?:\d+|\D+)\K~',
    $string,
    0,
    PREG_SPLIT_NO_EMPTY
)

Or you could use matched digits as the delimiter and retain the delimiters in the output.

preg_split(
    '~(\d+)~',
    $string,
    0,
    PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE 
)

A demonstration of both techniques.

---

If you know the order of your numeric and alphabetic substrings, then sscanf() is a perfect tool.

Code: (Demo)

var_export(sscanf('12jan', '%d%s'));

Output:

array (
  0 => 12,
  1 => 'jan',
)

Notice how 12 is conveniently cast as an integer as well.

sscanf() also allows individual variables to be assigned if desired ($day and $month) as the 3rd and 4th parameters.

Answer 7

Try This :

$string="12jan";
$chars = '';
$nums = '';
for ($index=0;$index<strlen($string);$index++) {
    if(isNumber($string[$index]))
        $nums .= $string[$index];
    else    
        $chars .= $string[$index];
}
echo "Chars: -$chars-<br>Nums: -$nums-";


function isNumber($c) {
    return preg_match('/[0-9]/', $c);
}