Question

I have two associative arrays that can look as follows:

$prod1 = (
    [name] = 'John',
    [address] = 'Milky way',
    [city] = 'Miami',
);

$prod2 = (
    [address] = 'Not so milky way'
);

$prod1 has always got the same kind of elements (name, address, city), but $prod2 could contain of either all of the elements or some of them

What I want is to replace the value in the elements in $prod1 that matches with the elements in $prod2. In the example above $prod2 contains of address, and therefore the address in $prod1 should be replaced with the address in $prod2 (the rest of the elements should of course stay as is).

How can this be accomplished?

Answer 1

The array_merge function will do this for you:

$prod_new = array_merge($prod1, $prod2);

From the documentation:

If the input arrays have the same string keys, then the later value for that key will overwrite the previous one.

Alternatively, you can use the + operator, which will give you the same result:

$prod_new = $prod1 + $prod2;

The + operator returns the right-hand array appended to the left-hand array; for keys that exist in both arrays, the elements from the left-hand array will be used, and the matching elements from the right-hand array will be ignored.