PHP中带有JSON对象的输出问题（可能是数组？）

Question

I'm having troubles getting a JSON object (possibly an array?) to output using PHP. My question is: How do I get only a displayName from the following (shortened) JSON object using PHP?

{"Response":
  {"results":
    [{"user":
      {"membershipId":"6343960","displayName":"J Raider"},"hasPendingApplication":false},
     {"user":
      {"membershipId":"4479502","displayName":"T Ellis"},"hasPendingApplication":false}]
  }
}

What I've tried so far:

var_dump($json); 
echo $json; 
echo $json->Response->results->user->displayName;
echo $json->Response->results[0]->user->displayName; 
echo $json->Response->results[0]->user[0]->displayName; 
echo json_encode($json, JSON_PRETTY_PRINT);
print_r($json)

My results have either been "null" "NULL" or simply no output. I am pulling from the Bungie API using the following code:

<?php 
    $apiKey = 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxx';

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, 'https://www.bungie.net/Platform/Group/1179713/Members/?lc=en&fmt=true&currentPage=1&platformType=1');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, array('X-API-Key: ' . $apiKey));

$json = json_decode(curl_exec($ch)); // edited to correct curl_init to  curl_exec

var_dump($json);

?>

I am aiming to do this as a web service using PHP. The Bungie API documentation says a JavaScript GET request will not work, so I'd like to stick with PHP for the request and the output.

To clarify my question: how do I use PHP to output the displayName from this JSON object?

Thanks in advance for your help and please let me know if I need to clarify anything.

Answer 1

Im pretty sure this is failing because you arent executing your curl post:

$json = json_decode(curl_init($ch));

should be

$json = curl_exec($ch);
$json = json_decode($json,true);
var_dump($json);