How do I flatten an associative array into an array with only values in PHP?
Solution 1
Your own solution is probably the cleanest solution, so converting it to a "one-liner":
$array = array('name' => 'aalaap','age' => 29, 'location' => 'mumbai');
$answer = array();
array_walk($array, create_function('$val,$key', 'global $answer; $answer[]=$key; $answer[]=$val;'));
var_dump($answer);
This avoids unnecessary and expensive array copies or sorting.
Alternatively, lose the global:
array_walk($array, create_function('$val,$key,$result', '$result[]=$key; $result[]=$val;'), &$answer);
Solution 2
PHP 5.3+ version of Just Jules' answer, and a bit more readable:
array_walk($array, function($val, $key) use (&$answer) {
$answer[] = $key;
$answer[] = $val;
});
Solution 3
I don't think this is possible - with the built-in functions you'll end up with all the keys then all the values:
$a = array('a' => 'A', 'b' => 'B', 'c' => 'C');
$a = array_merge(array_keys($a), array_values($a));
print_r($a);
You're going to have to use a loop like this:
$b = array();
foreach ($a as $key => $value)
{
$b[] = $key;
$b[] = $value;
}
Solution 4
It is possible, but I don't think it is more readable or any faster. It would work with a less-known feature of PHP - the array addition:
$array = array('name' => 'aalaap', 'age' => 29, 'location' => 'mumbai');
# Separate keys and values into distinct arrays
$keys = array_keys($array);
$values = array_values($array);
# Generate 2 new array containing indexes for the 2 arrays which contain
# only odd/even numbers:
$keysKeys = range(0, count($keys) * 2 - 1, 2);
$valuesKeys = range(1, count($keys) * 2, 2);
# Combine the keys with the values and add the results:
$array = array_combine($keysKeys, $keys) + array_combine($valuesKeys, $values);
# Sort the resulting array, otherwise the numbering will be broken
# (1,3,5,2,4,6)
ksort($array);
# Result:
var_dump($array);
array(6) {
[0]=>
string(4) "name"
[1]=>
string(6) "aalaap"
[2]=>
string(3) "age"
[3]=>
int(29)
[4]=>
string(8) "location"
[5]=>
string(6) "mumbai"
}
Comments
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aalaap almost 2 years
I have an array that has keys and values. For eg:
Array ( [name] => aalaap [age] => 29 [location] => mumbai )
I want to convert the keys from this into values, but I want the values to apear right after the keys. For eg:
Array ( [0] => name [1] => aalaap [2] => age [3] => 29 [4] => location [5] => mumbai )
I can easily write an iteration function that will do this... for eg:
array_flatten($arr) { foreach ($arr as $arrkey => $arrval) { $arr_new[] = $arrkey; $arr_new[] = $arrval; } return $arr_new; }
...but I'm trying to find out if there's any way this can be accomplished using
array_combine
,array_keys
,array_values
and/orarray_merge
, preferably in one, so i don't need to use a custom function.Is there?
-
jbasko almost 15 yearsI wonder why PHP does not have a function in global namespace called
array_flatten
. -
aalaap almost 15 yearsDo you think this is worth including in PHP natively?
-
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aalaap almost 15 yearsthis is just too much code for something that can already be done in two lines!
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aalaap almost 15 yearsI like this! My array_flatten function is probably a bit more intuitive to use, but I like this method! Thanks!
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aalaap almost 15 yearsKinda! I should have said <em>"<strong>easily</strong> accomplished"</em> :-)
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Willem Van Onsem almost 10 yearsAre such functions "compiled". Or are they processed at each single step?