Pass arguments from array in php to constructor

Question

Normally, if I want to pass arguments from $myarray to $somefunction I can do this in php using

call_user_func_array($somefunction, $myarray);

However this does not work when the function one wishes to call is the constructor for an object. For fairly obvious reasons it does not work to do:

$myobj = new call_user_func_array($classname, $myarray);

is there something fairly elegant that does work ?

Found a possible duplicate of How to "invoke" a class instance in PHP? after answering it.

Gordon · Accepted Answer · 2010-08-03 11:16:09Z

up vote 13 down vote accepted

You can use the Reflection API:

ReflectionClass::newInstanceArgs — Creates a new class instance from given arguments.

Example:

$reflector = new ReflectionClass('Foo');
$foo = $reflector->newInstanceArgs(array('foo', 'bar'));

answered Aug 3 '10 at 11:16

Gordon
108k10129224

	This seems like a good answer. Unfortunately, when I try it I get weird errors, ones I -don't- get when I do say: $foo = new Foo($arr[1],$arr[2]); I can't -really- do that though, because there's a variable and unknown amount of arguments in the array. – Agrajag Aug 3 '10 at 12:26
	@Agrajag you pass in one array that contains all arguments – Gordon Aug 3 '10 at 12:48
	Yes, that's precisely what I want to do -- and what call_user_func_array does. The problem is that I get an error about undefined call to CtCgiController() when I create a new object with the ReflectionClass whereas I don't get any problem when I create the very same object with new Classname(args...), this confuses me because my impression was that the two should be equivalent. – Agrajag Aug 4 '10 at 5:33
	@Agrajag weird indeed. Can you give the exaxt error message please? – Gordon Aug 4 '10 at 6:34
	The exact error is "Warning: Missing argument 1 for Module::Module() in /devel2/eivind/src/cp/cplib/Module.php on line 44", which is not really informative without the entire sourcecode. I'll investigate further, I guess it's possible that the ReflectionClass is merely somehow triggering an error that was really there all along. – Agrajag Aug 5 '10 at 6:07

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w3d · Answer 2 · 2010-08-03 11:20:27Z

up vote 1 down vote

Or, you could just pass the array directly?

$myObj = new $classname($myArray);

And read the elements of the array inside the method as if they are parameters to that method (the constructor in this case).

answered Aug 3 '10 at 11:20

w3d
2,2581422

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2 Answers