Get Array Values Recursively with PHP
I've been helping to write a WordPress plugin (I'm not ready to share it yet) and one of the tasks required is validating an array of user-selected values against a list of known valid values. The known valid array is actually a key=>value array so unfortunately array_values wont help get the simple list I'd like.
Instead a more advanced custom function was needed:
// http://php.net/manual/en/function.array-values.php
function array_values_recursive($array) {
$flat = array();
foreach($array as $value) {
if (is_array($value)) {
$flat = array_merge($flat, array_values_recursive($value));
}
else {
$flat[] = $value;
}
}
return $flat;
}
This recursive function dives into arrays, even key=>value arrays, to retrieve the final list of values. Thank you PHP.net!
![How to Create a Twitter Card]()
One of my favorite social APIs was the Open Graph API adopted by Facebook. Adding just a few META tags to each page allowed links to my article to be styled and presented the way I wanted them to, giving me a bit of control...
![I’m an Impostor]()
This is the hardest thing I've ever had to write, much less admit to myself. I've written resignation letters from jobs I've loved, I've ended relationships, I've failed at a host of tasks, and let myself down in my life. All of those feelings were very...
![Create a Twitter AJAX Button with MooTools, jQuery, or Dojo]()
There's nothing like a subtle, slick website widget that effectively uses CSS and JavaScript to enhance the user experience. Of course widgets like that take many hours to perfect, but it doesn't take long for that effort to be rewarded with above-average user retention and...
![Create a Trailing Mouse Cursor Effect Using MooTools]()
Remember the old days of DHTML and effects that were an achievement to create but had absolutely no value? Well, a trailing mouse cursor script is sorta like that. And I'm sorta the type of guy that creates effects just because I can.
No need to create a new array, just use iterators. There is an interface for iterators with values that can be iterators called RecursiveIterator. To wrap a nested array there is RecursiveArrayIterator. And to flatten an RecursiveIterator you can use RecursiveIteratorIterator, which by default only returns the leaves.
$it = new RecursiveIteratorIterator(new RecursiveArrayIterator($array)); foreach ($it as $k => $v) { var_dump("$k = $v"); }If you want to convert it to an array use iterator_to_array():
Although if you’re going to call
iterator_to_array()I think you’ve defeated your stated purpose for using iterators.I just love this blog, I always get to know something new. I didn’t know about this. Very useful!
function flatten_array($arg) { return is_array($arg) ? array_reduce($arg, function ($c, $a) { return array_merge($c, flatten_array($a)); },[]) : [$arg]; }