<?php
// the name and value must be enclosed in double quotes
// single quotes are not valid
$bad_json = "{ 'bar': 'baz' }";
echo "BAD:" . json_decode($bad_json); // null
$good_json = '{ "baz": "bar" }';
echo "GOOD" . json_decode($good_json);
BAD:
Fatal error: Uncaught Error: Object of class stdClass could not be converted to string in /in/4al55:9
Stack trace:
#0 {main}
thrown in /in/4al55 on line 9
Process exited with code 255.