PHP - ReflectionFunction - 函数Test :: test_function（）不存在

I could use RefexionFunction outside of a class, but inside a class I get an exception.

Fatal error: Uncaught ReflectionException: Function Test::test_function() does not exist in test.php.

<?php

function parameters($functionName,$args){
    $f = new ReflectionFunction($functionName);
    ....
}


class Test{
    public function test_functionA($abc,$d,$e,$f) {
        parameters(__METHOD__,func_get_args()); 
    }

    protected function test_functionB($abc,$d,$e,$f) {
        parameters(__METHOD__,func_get_args()); 
    }

    private function test_functionC($abc,$d,$e,$f) {
        parameters(__METHOD__,func_get_args()); 
    }
}

$test = new Test();
$test->test_function('something',1,2,array(123,456));

?>

Appreciate your help.

Your error:

Fatal error: Uncaught ReflectionException: Function Test::test_function() does not exist in test.php.

Doesn't refer to the function name quite as you expect it to.

ReflectionClass docs says this:

The ReflectionClass class reports information about a class.
ref: https://secure.php.net/manual/en/class.reflectionclass.php

You want to use a combination of methods available in that class to get information about the passed method like this:

public function parameters($class, $fnc)
{
    $f = new ReflectionClass($class);

    if ($f->hasMethod($fnc)) {
        return 'howdy folks';
    } else {
        return 'not so howdy folks';
    }
}

You first pass the class before checking if the function exists. You can then use the built-in function hasMethod to check if the function exists. You then use the parameters function like this:

public function testFunction()
{
    return $this->helper->parameters(__CLASS__, __FUNCTION__);
}

All together the code looks like this:

<?php
    ini_set('display_startup_errors', 1);
    ini_set('display_errors', 1);
    error_reporting(-1);

    class paramsHelper
    {
        public function parameters($class, $fnc)
        {
            $f = new ReflectionClass($class);
            $f->getMethod($fnc);

            if ($f->hasMethod($fnc)) {
                return 'howdy folks';
            } else {
                return 'not so howdy folks';
            }

            return $f;
        }
    }

    class Test
    {
        protected $helper;

        public function __construct($helper)
        {
            $this->helper = $helper;
        }

        public function testFunction()
        {
            return $this->helper->parameters(__CLASS__, __FUNCTION__);
        }
    }

    $test = new Test(new paramsHelper());

    echo '<pre>';
    print_r($test->testFunction());
    echo '</pre>';

One of your other problems is that __METHOD__ actually returns a string like this: Test::testFunction not testFunction - hence my use of __FUNCTION__ instead.

Edit:

To get the parameters of the passed method, change your parameters method to this:

class paramsHelper
{
    public function getMethodParameters($class, $fnc)
    {
        $f = new ReflectionMethod($class, $fnc);

        echo '<pre>';
        print_r($f->getParameters());
        echo '</pre>';
    }
}

This uses ReflectionMethod in place of ReflectionClass - this is more inline with your intended use.

ref: https://secure.php.net/manual/en/class.reflectionmethod.php

use:

class paramsHelper
{
    public function getMethodParameters($class, $fnc)
    {
        $f = new ReflectionMethod($class, $fnc);

        echo '<pre>';
        print_r($f->getParameters());
        echo '</pre>';
    }
}

class Test
{
    protected $helper;

    public function __construct($helper)
    {
        $this->helper = $helper;
    }

    public function testFunction($a = '', $b = 1, $c = 3)
    {
        return $this->helper->parameters(__CLASS__, __FUNCTION__);
    }
}

$test = new Test(new paramsHelper());

echo '<pre>';
print_r($test->testFunction());
echo '</pre>';