Is it possible in php to make an array an array key as well?
Example:
array(
array('sample', 'abc') => 'sample value'
);
4 Answers
No, if you read the manual
An array in PHP is actually an ordered map. A map is a type that associates values to keys. This type is optimized for several different uses; it can be treated as an array, list (vector), hash table (an implementation of a map), dictionary, collection, stack, queue, and probably more. As array values can be other arrays, trees and multidimensional arrays are also possible.
And :
The key can either be an integer or a string. The value can be of any type.
Comments
This is not possible - array keys must be strings or integers.
What you could do is use serialize:
$myArr = array( serialize(array('sample', 'abc')) => 'sample value');
Which will be the same as:
$myArr = array( 'a:2:{i:0;s:6:"sample";i:1;s:3:"abc";}' => 'sample value');
and could be accessed like:
echo $myArr[serialize(array('sample', 'abc'))];
But note that the serialised string which would be the unique identifier for the array item is clearly fairly complicated and almost impossible to type by hand.
3 Comments
Erik
This is so scary to look at...
Aldee
yes.. scary but efficient i think.. thanks..
Robin Winslow
Not efficient enough to be the accepted answer? ;)
PHP arrays can contain integer and string keys while since PHP does not distinguish between indexed and associative arrays. Look for php manual Php Manual
Comments
whats wrong with
array(
'sample value' => array('sample', 'abc')
);
you could then do
foreach($array as $string => $child){
...
}
and use the $child for whatever purpose
serialize()the array into a string to use as an array key, but I can't see why your design would require this and I don't actually advocate doing it. It would be fraught with problems, like having to reserialize every time you needed to change it.integerandkeysonly..SplObjectStoragefor that though.