php: how to get associative array key from numeric index?

php key associative-array
Mazatec picture Mazatec · Nov 4, 2010 · Viewed 115.7k times · Source

If I have:

$array = array( 'one' =>'value', 'two' => 'value2' );

how do I get the string one back from $array[1] ?

Answer

deceze picture deceze · Nov 4, 2010

You don't. Your array doesn't have a key [1]. You could:

  • Make a new array, which contains the keys:

    $newArray = array_keys($array);
echo $newArray[0];

    But the value "one" is at $newArray[0], not [1].
    A shortcut would be:

    echo current(array_keys($array));

  • Get the first key of the array:

     reset($array);
 echo key($array);

  • Get the key corresponding to the value "value":

    echo array_search('value', $array);

This all depends on what it is exactly you want to do. The fact is, [1] doesn't correspond to "one" any which way you turn it.

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