call_user_func_array

Call a callback with an array of parameters

&reftitle.description; `mixed` `call_user_func_array` `callable` `callback` `array` `args`

Calls the `callback` given by the first parameter with the parameters in `args`.

&reftitle.parameters;

`callback`

- The `callable` to be called.

`args`

- The parameters to be passed to the callback, as an array.

  If the keys of `args` are all numeric, the keys are ignored and each element will be passed to `callback` as a positional argument, in order.

  If any keys of `args` are strings, those elements will be passed to `callback` as named arguments, with the name given by the key.

  It is a fatal error to have a numeric key in `args` appear after a string key, or to have a string key that does not match the name of any parameter of `callback`.

&reftitle.returnvalues;

Returns the return value of the callback, or &false; on error.

&reftitle.changelog;

&Version; | &Description;
8.0.0 | `args` keys will now be interpreted as parameter names, instead of being silently ignored.

&reftitle.examples;

### `call_user_func_array` example

    <?php
    function foobar($arg, $arg2) {
        echo __FUNCTION__, " got $arg and $arg2\n";
    }
    class foo {
        function bar($arg, $arg2) {
            echo __METHOD__, " got $arg and $arg2\n";
        }
    }

    // Call the foobar() function with 2 arguments
    call_user_func_array("foobar", array("one", "two"));

    // Call the $foo->bar() method with 2 arguments
    $foo = new foo;
    call_user_func_array(array($foo, "bar"), array("three", "four"));
    ?>

&example.outputs.similar;

    foobar got one and two
    foo::bar got three and four

### `call_user_func_array` using namespace name

    <?php

    namespace Foobar;

    class Foo {
        static public function test($name) {
            print "Hello {$name}!\n";
        }
    }

    call_user_func_array(__NAMESPACE__ .'\Foo::test', array('Hannes'));

    call_user_func_array(array(__NAMESPACE__ .'\Foo', 'test'), array('Philip'));

    ?>

&example.outputs.similar;

    Hello Hannes!
    Hello Philip!

### Using lambda function

    <?php

    $func = function($arg1, $arg2) {
        return $arg1 * $arg2;
    };

    var_dump(call_user_func_array($func, array(2, 4)));

    ?>

&example.outputs;

    int(8)

### Passing values by reference

    <?php

    function mega(&$a){
        $a = 55;
        echo "function mega \$a=$a\n";
    }
    $bar = 77;
    call_user_func_array('mega',array(&$bar));
    echo "global \$bar=$bar\n";

    ?>

&example.outputs;

    function mega $a=55
    global $bar=55

### `call_user_func_array` using named arguments

    <?php
    function foobar($first, $second) {
        echo __FUNCTION__, " got $first and $second\n";
    }

    // Call the foobar() function with named arguments in non-positional order
    call_user_func_array("foobar", array("second" => "two", "first" => "one"));

    // Call the foobar() function with one named argument
    call_user_func_array("foobar", array("foo", "second" => "bar"));

    // Fatal error: Cannot use positional argument after named argument
    call_user_func_array("foobar", array("first" => "one", "bar"));

    ?>

&example.outputs.similar;

    foobar got one and two
    foobar got foo and bar

    Fatal error: Uncaught Error: Cannot use positional argument after named argument

&reftitle.notes; ¬e.func-callback-exceptions;
&reftitle.seealso;

- `call_user_func`
- `ReflectionFunction::invokeArgs`
- `ReflectionMethod::invokeArgs`