Display php array element from a function - php

Question

Hello I have the following array that is a result form a function that is being called based on (isset)
function: list_activity_details_array() returns:
{"activity_related_to_id":"2","activity_id":"14","activity_type_icon":"fa fa-phone","activity_title":"call","activity_created_by":"User Last","activity_create_date":"03-08-2015","activity_due_date":"04-01-2015","acitvity_url_param":"contact_id","activity_details":"email and call details"})
How can I view the array element in html. for example. if the field is activity_details. How can I only view the activity_details by calling the function and the element?
Here is the code that shows the array:
function list_activity_details_array(){
global $connection;
//$contact_id = $_REQUEST['contact_id'];
$activity_id = $_REQUEST['activity_id'];
$get = "SELECT * FROM activity_base WHERE activity_id = '$activity_id' "
or die("Error: ".mysqli_error($connection));
$query = mysqli_query($connection, $get);
//Get activity base information
$activity_array = array();
while ($activity = mysqli_fetch_array($query)){
$activity_related_to_id = $activity ['activity_related_to_id'];
$activity_id = $activity['activity_id'];
$activity_type_id = $activity['activity_type_id'];
$activity_entity_type_id = $activity['activity_entity_type_id'];
$activity_title = $activity['activity_title'];
$activity_created_by = $activity['activity_created_by'];
$activity_status_code_id = $activity['activity_status_code_id'];
//$activity_type_icon;
//Reverse Date
$activity_create_date = date("m-d-Y", strtotime($activity['activity_created_on']));
$activity_due_date = date("m-d-Y", strtotime($activity['activity_due_date']));
if ($activity_type_id == "1"){
$activity_type_icon = "fa fa-envelope";
}else if ($activity_type_id == "3"){
$activity_type_icon = "fa fa-suitcase";
}else if ($activity_type_id == "2"){
$activity_type_icon = "fa fa-phone";
}
if ($activity_entity_type_id == "1") {
$acitvity_url_param = "acct_id";
$acitivty_is_for ="accounts_base";
//$page_url = "account-profile.php";
}else if ($activity_entity_type_id == "2") {
$acitvity_url_param = "contact_id";
$acitivty_is_for ="contacts";
//$page_url = "contact-profile.php";
}else if ($activity_entity_type_id == "3") {
$acitvity_url_param = "contact_id";
$acitivty_is_for ="contacts";
//$page_url = "contact-profile.php";
}
//Get detailed activity information
//If activity is Email
if ($activity_type_id == "1") {
$email_details = email_activity_details($activity_id);
while ( $email = mysqli_fetch_assoc($email_details)) {
$activity_details = nl2br($email['email_message']);
}
}else if ($activity_type_id == "2") {
$call_details = call_activity_details($activity_id);
while ( $call = mysqli_fetch_assoc($call_details)) {
$activity_details = $call['call_details'];
}
}else if ($activity_type_id == "3") {
$meeting_details = meeting_activity_details($activity_id);
while ( $meeting = mysqli_fetch_assoc($meeting_details)) {
$activity_details = $meeting['meeting_details'];
}
}
//Get creator user info
$user_query = get_user_info($activity_created_by);
while ($user = mysqli_fetch_array($user_query)) {
$activity_created_by = $user['user_full_name'];
}
$activity_array['activity_related_to_id'] = $activity['activity_related_to_id'];
$activity_array['activity_id'] = $activity['activity_id'];
$activity_array['activity_related_to_id'] = $activity['activity_related_to_id'];
$activity_array['activity_type_icon'] = $activity_type_icon;
$activity_array['activity_title'] = $activity['activity_title'];
$activity_array['activity_created_by'] = $activity_created_by;
$activity_array['activity_create_date'] = $activity_create_date;
$activity_array['activity_due_date'] = $activity_due_date;
$activity_array['acitvity_url_param'] = $acitvity_url_param;
$activity_array['activity_details'] = $activity_details;
$activity_array['activity_title'] = $activity['activity_title'];
$encode = json_encode($activity_array);
print_r($encode);
}
}
if (isset($_REQUEST['activity_id'])) {
list_activity_details_array();
}

Answer 1

Looks like JSON to me so you'll need to
$foo = json_decode($output);
Which then should allow you to refer to:
echo $foo['activity_related_to_id'];
// Outputing 2