Regex to extract (austrian) street housenumber/stairs/floor/door

I need to extract the housenumber with all the different constellations in austria:

|               Street name               | housenumber | stairs | floor | door |
| --------------------------------------- | ----------- | ------ | ----- | ---- |
| Lilienstr. 12a                          | 12a         |        |       |      |
| Leibnizstraße 36/28/2                   | 36          | 28     |       | 2    |
| Prager Straße 14/3/1/4                  | 14          | 3      | 1     | 4    |
| Guentherstr. 43 B                       | 43 B        |        |       |      |
| Eberhard-Leibnitz Str. 1/7              | 1           |        |       | 7    |
| Schießstätte 7/7                        | 7           |        |       | 7    |

I’ve already found this question: Regex to extract (german) street number.

This works if no stair/floor/door is entered. Can you help?

^[ -0-9a-zA-ZäöüÄÖÜß.]+?s+(d+(s?[a-zA-Z])?)s*(?:$|(|[A-Z]{2})

Answer

Not knowing Austrian address formats it’s hard for me to say if this is correct, however, please see the regex below.

^(.*)s+(d+(?:s*[a-zA-Z])?)(?:/(d+))?(?:/(d+))?(?:/(d+))?s*(?:$|(|[A-Z]{2})

This expression will always match all 4 number groups (1/2/3/4) so you will need to do some additional processing to determin if an address has a housenumber and stairs and floor and door, compared to if an address only has a housenumber and door.

For example:

<?php

$pattern = '^(.*)s+(d+(?:s*[a-zA-Z])?)(?:/(d+))?(?:/(d+))?(?:/(d+))?s*(?:$|(|[A-Z]{2})$';

$addresses = [
    'Lilienstr. 12a',
    'Leibnizstraße 36/28/2',
    'Prager Straße 14/3/1/4',
    'Guentherstr. 43 B',
    'Eberhard-Leibnitz Str. 1/7',
    'Schießstätte 7/7'
];

$results = [];

foreach ( $addresses as $address ) {
    
    // 0. Full match
    // 1. Streetname
    // 2. Housenumber
    // 3. Stairs
    // 4. Floor
    // 5. Door
    preg_match( '/' . $pattern . '/', $address, $matches );

    // Remove full match from 
    array_shift( $matches );
    
    // Set up default values
    $streetname = array_shift( $matches );
    $housenumber = null;
    $stairs = null;
    $floor = null;
    $door = null;

    // Count total values given
    $total = count( array_filter( array_map( 'trim', $matches ) ) );

    switch ( $total ) {

        // Has all 4 parts
        case 4:
            $housenumber = $matches[ 0 ];
            $stairs = $matches[ 1 ];
            $floor = $matches[ 2 ];
            $door = $matches[ 3 ];
            break;

        // Only has 3 parts
        case 3:
            $housenumber = $matches[ 0 ];
            $stairs = $matches[ 1 ];
            $door = $matches[ 2 ];
            break;

        // Only has 2 parts
        case 2:
            $housenumber = $matches[ 0 ];
            $door = $matches[ 1 ];
            break;

        // Has 1 part
        default:
            $housenumber = $matches[ 0 ];
            break;
    }

    // Add to results array
    $results[] = [
        'address' => $address,
        'streetname' => $streetname,
        'housenumber' => $housenumber,
        'stairs' => $stairs,
        'floor' => $floor,
        'door' => $door
    ];

}

print_r( $results );

Output

Array
(
    [0] => Array
        (
            [address] => Lilienstr. 12a
            [streetname] => Lilienstr.
            [housenumber] => 12a
            [stairs] => 
            [floor] => 
            [door] => 
        )

    [1] => Array
        (
            [address] => Leibnizstraße 36/28/2
            [streetname] => Leibnizstraße
            [housenumber] => 36
            [stairs] => 28
            [floor] => 
            [door] => 2
        )

    [2] => Array
        (
            [address] => Prager Straße 14/3/1/4
            [streetname] => Prager Straße
            [housenumber] => 14
            [stairs] => 3
            [floor] => 1
            [door] => 4
        )

    [3] => Array
        (
            [address] => Guentherstr. 43 B
            [streetname] => Guentherstr.
            [housenumber] => 43 B
            [stairs] => 
            [floor] => 
            [door] => 
        )

    [4] => Array
        (
            [address] => Eberhard-Leibnitz Str. 1/7
            [streetname] => Eberhard-Leibnitz Str.
            [housenumber] => 1
            [stairs] => 
            [floor] => 
            [door] => 7
        )

    [5] => Array
        (
            [address] => Schießstätte 7/7
            [streetname] => Schießstätte
            [housenumber] => 7
            [stairs] => 
            [floor] => 
            [door] => 7
        )

)

See here: http://sandbox.onlinephpfunctions.com/code/3952b2f3cab251e7137bcd9d55e42d8c8bcdd723