[SOLVED] What does this line of code do?

[fluvly]

I found this line of code, but I can't understand the syntax of it:

 

register_shutdown_function(array($this, 'close'));

 

I read on the online documentation that the register_shutdown_function calls a shutdown function before the script ends; it's not the actual function that I have a problem with, but the syntax of the shutdown function between parenthesis:

 

array($this, 'close')

 

 

What does that mean? What happens in this case when the register_shutdown_function is called? What function does it call? An array? I thank in advance anyone who is able to help.

 

[Mark Baker]

It calls a class method. The first element in the array identifies an instantiated class object ($this, the instantiated object in which the shutdown function is defined), the second element identifies the method by name ('close')

[fluvly]

Thank you for the explanation, and now one side of it is clear. But I still don't understand why those 2 elements are put in an array... shouldn't there be just the name of the function? Something like:

 

register_shutdown_function($this->close);

 

It might be a banal doubt, but I'm new to php and I really can't understand the "array" bit. Thanks!

 

[Mark Baker]

Thank you for the explanation, and now one side of it is clear. But I still don't understand why those 2 elements are put in an array... shouldn't there be just the name of the function? Something like:

 

register_shutdown_function($this->close);

It would simply be the name of a function if the code was procedural, but it's not - it's OOP. Using an array like this is the standard mechanism that PHP uses for a lot of callbacks when the method is defined within a class.