Pluck Fields Out Of an Object or Array

Some days ago I was working on a project and I needed to get out of an object some data, but not all of them. Specifically, I had many terms, and I needed to get only the key name from that object.

What I would have done, is looping though all the items and build an array from that with their names. But I learned about a better way!

Meet wp_list_pluck

wp_list_pluck is a default WordPress function that plucks a certain field out of an object or an array. It’s very easy to use, look at this example:

If you check what $foods contains now you will get this:

array(
    'Banana',
    'Apple',
    'Lettuce',
    'Apple'
);

What happened here is that the function extracted all the names from the multi-dimensional array and created a new array with only those names.

The same could be done with objects.

You also need to know that wp_list_pluck supports a third parameter. You can specify another key from the original array that will be used as key for the values in the new array. Looking at the example above, if I use $foods = wp_list_pluck( $foods, 'name', 'id' ); I’d get this array as result:

array(
    4 => 'Banana',
    5 => 'Apple',
    2 => 'Lettuce',
    7 => 'Apple'
);

As you can see, the value of the id from the original array is now used as a key for the corresponding name in the new array.