php - find match in string

Question

I'm trying to work out how to find a match in a string. I'm looking for a match on any of the following - = ? [] ~ # ! 0 - 9 A-Z a-z and I need to know what its matched on .

Eg: matched on !, or matched on = and # and ?

Normally I'd use this:

$a = 'How are you?';

if (strpos($a, 'are') !== false) {
    echo 'true';
}

However I'm not sure how to do that so it looks up the characters needed. Also where I may have [], It could be [] or [xxxx] where xxxx could be any number of alpha numeric characters.

I need to match and any of the characters listed, return the characters so I know what was matched and if the [] contain any value return that as well.

Eg:

$a = 'DeviceLocation[West12]'; Would return: $match = '[]'; $match_val= 'West12';

$a = '#=Device'; Would return:$match = '#,=';

$a= '?[1234]=#Martin'; Would return: $match = '?, [], =, #'; $match_val= '1234';

Can any one advise how I can do this. Thanks

`DeviceLocation[West12]` what do you want to find in this string ? — Owais Aslam, Oct 04 '16 at 08:58
Try `if (preg_match('/[][A-Za-z0-9!#~?=-]/', $str, $m)) { echo "Matched: " . $m[0]; }` — Wiktor Stribiżew, Oct 04 '16 at 08:59
@OwaisArain - I'd want to match on the [] and if possible grab the value from between. — Rocket, Oct 04 '16 at 09:01
So, you only need the string between square brackets? See https://ideone.com/8L3naA — Wiktor Stribiżew, Oct 04 '16 at 09:02
I need to match and any of the characters listed, return the characters so I know what was matched and if the [] contain any value return that as well. — Rocket, Oct 04 '16 at 09:04
That just shows 'D' - I've updated my answer with some examples. — Rocket, Oct 04 '16 at 09:07
Of course it ouptuts `D` because it matches *any of the characters listed*. You forgot to add the expected output for each input. — Wiktor Stribiżew, Oct 04 '16 at 09:07
I've updated the original question with examples and expected output. — Rocket, Oct 04 '16 at 09:10

score 1 · Answer 1 · answered Oct 04 '16 at 08:58

1

Please use Regular Expressions, e.g using preg_match

answered Oct 04 '16 at 08:58

Mateusz Palichleb

765
12
20

Owais Aslam · Answer 2 · 2016-10-04T09:32:13.800

1

Try this

It will match the string in []

preg_match_all("/\[([^\]]*)\]/", $text, $matches);

And this will match string after ? and #=

preg_match_all("/^#=(\S+)|\?(.*)/", $text, $matches);

var_dump($matches);

edited Oct 04 '16 at 09:32

answered Oct 04 '16 at 09:06

Owais Aslam

1,577
1
17
39

OP does not need to extract all texts inside square brackets. See the question: *Eg: matched on `!`, or matched on `=` and `#` and `?`* – Wiktor Stribiżew Oct 04 '16 at 09:09

score 1 · Accepted Answer · answered Oct 04 '16 at 10:44

1

Well, that requirements are a bit vague, but that is what I deduced:

1) if there is an alphanumeric string inside square brackets get it as a separate value
2) all other mentioned chars should be matched one by one and then imploded.

You may use the following regex to get the values you need:

$re = '@\[([a-zA-Z0-9]+)\]|[][=?~#!]@';

Details:

\[ - a [
([a-zA-Z0-9]+) - Group 1 value capturing 1 or more alphanumeric symbols
\] - a closing ]
| - or
[][=?~#!] - a single char, one of the defined chars in the set.

See the regex demo. The most important here is the code that gets the matches (feel free to adapt):

$re = '@\[([a-zA-Z0-9]+)\]|[][=?~#!]@';
$strs =array('DeviceLocation[West12]', '#=Device', '?[1234]=#Martin');

foreach ($strs as $str) {
    preg_match_all($re, $str, $matches, PREG_SET_ORDER);
    $results = array();
    $match_val = "";
    foreach ($matches as $m) {
        if (!empty($m[1])) {
            $match_val = trim($m[1], "[]");
            array_push($results, "[]");
        } else {
            array_push($results, $m[0]);
        } 
    }
    echo "Value: " . $match_val . "\n";
    echo "Symbols: " . implode(", ", $results);
    echo "\n-----\n";
}

See the PHP demo

Output:

Value: West12
Symbols: []
-----
Value: 
Symbols: #, =
-----
Value: 1234
Symbols: ?, [], =, #
-----

answered Oct 04 '16 at 10:44

Wiktor Stribiżew

607,720
39
448
563

1

that looks perfect. Thank you. – Rocket Oct 04 '16 at 13:38
I'd like to turn this into a function. How do I return the Value and Symbols separately ? – Rocket Oct 04 '16 at 13:47
You may return an array. See http://stackoverflow.com/questions/3451906/multiple-returns-from-function. – Wiktor Stribiżew Oct 04 '16 at 13:51
Just thought of one other possible scenario.. `[Device]=test` Is there anyway to get the word test as well in a new variable ? – Rocket Oct 04 '16 at 13:59
1

If you mean you want to get chunks of word chars as yet another variable, you may try adding another capture group alternative `(\w+)`. See https://ideone.com/OfBfK4. Note how the output also changes for other test strings. – Wiktor Stribiżew Oct 04 '16 at 14:02
wow.. thanks. looking at that symbols is always the symbols found. Val 1 is the value from the brackets and val2 is other text.. That will work. Thanks again – Rocket Oct 04 '16 at 14:06

score 0 · Answer 4 · answered Oct 04 '16 at 08:58

0

You need regular expressions to check for any text inside another with different properties, here is a simple tutorial on that link.

answered Oct 04 '16 at 08:58

Ricardo Ortega Magaña

2,403
16
23

php - find match in string

4 Answers4