PHP，闭包和提取参数

Question

I'm not sure how to best title this so I thought I would post an example of what I'm trying to achieve. I've super-simplified this for now.

So first is the very basic class that will do the action.

abstract class AuditedSave extends AuditedSaveImplementation
{

    public static function run($callback = null)
    {
        return new AuditedSaveImplementation($callback);
    }

}

class AuditedSaveImplementation
{

    public function __construct(Closure $closure)
    {
        echo ' - I ran before'; // point 1, $test = 0
        $closure();
        echo ' - i ran after!'; // point 2, $test = 1
    }

}

Then the code that calls it.

$test = 0;

AuditedSave::run(function() use ($test)
{
    $test = 1;
});

So between point 1 and 2 as commented, the closure runs and would set the value of $test to 1. However, I want to store the value of whatever is passed as the first parameter (in this case, $test ) as a copy of what it was at the time of function calling - which will always run, the closure then modifies it (this is the part that can be variable), and then afterwards a comparison gets made and actions happen based on differences - which will always run.

However, in order to do this, I need to be able to access the $test variable within the __construct() method of AuditedSaveImplementation without knowing what it's called.

Is this possible at all?

Answer 1

You can use ReflectionFunction class getStaticVariables method to get params passed to closure via use . Like this:

class AuditedSaveImplementation
{

    public function __construct(Closure $closure)
    {
        echo ' - I ran before'; // point 1, $test = 0
        $closureReflection = new ReflectionFunction($closure);
        $variables = $closureReflection->getStaticVariables();
        var_dump($variables);
        $closure();
        echo ' - i ran after!'; // point 2, $test = 1
    }

}

But as mentioned in the comments you should rethink how you do this. It's not a good approach. Try to create a special class as was suggested in comments.