如何从另一个数组的值创建一个数组

Question

This is probably a question with a very simple answer but I am unable to figure it out. How could I write a foreach loop to add elements from an array to another array? Below I have array $A and I want to be able to write code to come up with something like $B from $A.

$A = array('0'=>array('name'=>'Oscar'),'1'=>array('name'=>'Jake'));

$B = array('0'=>'Oscar','1'=>'Jake');

Here is what I came up with, but it's not working.

$B = array();
foreach ($A as $element=>$data) {
    $B[] = $element['name'];
}

Answer 1

This should work:

$b = array_map(function($content) {
    return $content['name'];
}, $a);

array_map is a method with a callback that loops over an array and creates a new loop, depending on the return value in the function .

I use array_map instead of a foreach loop, because array methods of PHP are optimized and improve performance when used right.

Docs about array_map can be found here .

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What I always like to do, is visualize it for myself.

You can use multiple ways to visualize how the variable looks like and go from there. My personal favorites:

• debugging using Xdebug
• print_r()
• var_dump()