php in_array() not matching

Question

The first array is called $related_docs and the second on is $all_docs. I'm trying to match the "1" value in the first array with the "1" value in the second array.

    Array
(
    [0] => 1
)
Array
(
    [0] => Array
        (
            [id] => 1
            [type_name] => bla1
        )

    [1] => Array
        (
            [id] => 2
            [type_name] => bla2
        )

    [2] => Array
        (
            [id] => 3
            [type_name] => bla3
        )
    )

I'm trying to see if any values from the first array occur in the second array, which it does, but the script prints out nothing but "no". Why is that? I've tried changing $all_docs in the if() statement to $a but that makes no difference.

foreach($all_docs as $a)
  {
   if( in_array($related_docs, $all_docs) )   
   {
    print "yes";
   }
   else print "no";
  }

Do I need to search recursively in the second array?

Pekka · Accepted Answer · 2010-03-06 14:05:27Z

2

You are trying to do a recursive search, which in_array() can't do. It can only very primitively match against the first level of the array you search in.

Maybe this implementation of a recursive in_array() works for what you need.

Alternatively, use something along the lines of:

function id_exists ($search_array, $id)
 {
   foreach ($search_array as $doc)
    if ($doc["id"] == $id) return true;

   else return false;

 }

foreach($all_docs as $a)
  {
   if(  id_exists($related_docs, $a) )   
   {
    print "yes";
   }
   else print "no";
  }

edited Mar 6, 2010 at 14:05

answered Mar 6, 2010 at 13:50

Pekka

451k150 gold badges989 silver badges1.1k bronze badges

Sign up to request clarification or add additional context in comments.

4 Comments

stef Over a year ago

Thanks for the suggestion but that recursive search function doesn't work either.

Pekka Over a year ago

@stef I think the best thing is for you to write a custom function that loops through $all_docs and returns true if $all_docs[i]["id"] == $search_id.

moo Over a year ago

@stef this is the most logical answer

stef Over a year ago

OK, this works after I changed $doc['id'] = $id to $doc['id'] = $id['id']. Thank you Pekka.

moo · Accepted Answer · 2010-03-06 14:12:21Z

2

function in_array_multiple(array $needles, array $haystacks) {
foreach($haystacks as $haystack) {
    foreach($needles as $needle) {
        if(in_array($needle, $haystack)) {
            return true;
        }
    }
}
return false;
}

(This is an iterative function, not a recursive one.)

answered Mar 6, 2010 at 14:12

moo

7,8379 gold badges46 silver badges40 bronze badges

Comments

Gordon · Accepted Answer · 2010-03-06 14:32:48Z

1

Try

$a = array(1);
$b = array(
    array('id' => 1, 'type_name' => 'bla1'),
    array('id' => 2, 'type_name' => 'bla2'),
    array('id' => 3, 'type_name' => 'bla3'),
);

Checking if ID in $b exists in $a, so it's the other way round than you described it, but it shouldn't matter for the outcome:

foreach($b as $c) {
    echo in_array($c['id'], $a) ? 'yes' : 'no';
}

It's not generic, but it does what you want.

edited Mar 6, 2010 at 14:32

answered Mar 6, 2010 at 14:09

Gordon

318k76 gold badges548 silver badges566 bronze badges

Collectives™ on Stack Overflow

php in_array() not matching

3 Answers 3

4 Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

4 Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related