Since upgrading a legacy application from PHP7 to PHP8, I’ve found a change in behaviour with json_encode. Given the following array:

$values = ["a"="a","b"="1"];
$valuesEncoded = json_encode($values);

returns:

{a:"a",b:1}

when in PHP7 it used to return:

{a:"a",b:"1"}

It is causing very many issues when I’m using Javascript to read the result and it’s expecting a string not a number.

I’ve investigated using the flags but the nearest I can find relating to this is JSON_NUMERIC_CHECK which gives the behaviour I’m getting by default, and is the opposite of what I need.

How do I get json_encode to behave like it used to?