What potential issues can arise when attempting to loop through JSON data in PHP?

One potential issue when looping through JSON data in PHP is that the JSON data may be malformed or invalid, causing errors when attempting to decode it. To solve this, you can use the `json_decode()` function with the second parameter set to `true` to return an associative array instead of an object. This way, you can easily loop through the JSON data using a `foreach` loop.

$jsonData = '{"key1": "value1", "key2": "value2"}';
$arrayData = json_decode($jsonData, true);

foreach ($arrayData as $key => $value) {
    echo $key . ': ' . $value . PHP_EOL;
}