Determining the amount of parameters a function requires from outside of the func

PHP
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I’m looking for a way to determine the amount of parameters a function requires from outside of the function. “func_get_args” works only within a function, so it wont work. The purpose I have in mind is a request router that looks for class methods based on a url supplied, and then supplies the remaining arguments to the method as given by the url. But the method currently can be called even if an invalid number of parameters/arguments is supplied, leading to errors.

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To be clear: by “outside of the function,” I mean outside of the function’s scope.

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Hi ShinVe,

Good question. It turns out that you can check the number of arguments that a function accepts using PHP’s Reflection classes:


$refFunc = new ReflectionFunction('preg_replace');
echo $refFunc->getNumberOfParameters();

// Outputs: 5
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Thank you!

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