“At sign” @ in SimpleXML object?

Question 1

This is the output of print_r() run on a typical SimpleXMLElement object:

SimpleXMLElement Object
(
    [@attributes] => Array
        (

        )
)

What does the @ sign mean?

Question 2

This is a SimpleXMLElement object. The '@attributes' row is an internal representation of the attributes from the XML element. Use SimpleXML's functions to get data from this object rather than interacting with it directly.

Question 3

if($A->b->c != null) //c exists

If c does not exist, its value will be null (or, to be more precise, it will have no value). Note, however, that for this to work, both A and b need to not be null. Otherwise, PHP will throw an error (I think).

Question 4

Cast as whatever type you want (and makes sense...). By concatenating, you're implicitly casting to string, so

$value = (string) $xml->someNode->innerNode;

Question 5

The problem for me was that I forgot to verify my domain under the Service Id section of the Apple dev portal.

You need to download the key they give you, and upload it to: https://example.com/.well-known/apple-developer-domain-association.txt

The website doesn't verify automatically, you have to click the verify button and get a green tick next to the domain to be sure. After this, I had no more invalid_client issues.

Update 2020.07

As the flow was changed, you just have to add the Domain and the Communication Email to:

Certificates, Identifiers & Profiles > More > Configure

Question 6

At symbol - @

The @ symbol tells the command processor to be less verbose; to only show the output of the command without showing it being executed or any prompts associated with the execution. When used it is prepended to the beginning of the command, it is not necessary to leave a space between the "@" and the command.

When "echo" is set to "off" it is not necessary to use "@" because setting "echo" to "off" causes this behavior to become automatic. "Echo" is usually set to "on" by default when the execution of a script begins. This is the reason "@echo off" is commonly used, to turn echo off without displaying the act of turning it off.

echo verbose
@echo less verbose
pause

“At sign” @ in SimpleXML object?

Answers

Update 2020.07

php,simplexml