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forward_static_call

(PHP 5 >= 5.3.0, PHP 7, PHP 8)

forward_static_callCall a static method

Description

forward_static_call(callable $callback, mixed ...$args): mixed

Calls a user defined function or method given by the callback parameter, with the following arguments. This function must be called within a method context, it can't be used outside a class. It uses the late static binding.

Parameters

callback

The function or method to be called. This parameter may be an array, with the name of the class, and the method, or a string, with a function name.

args

Zero or more parameters to be passed to the function.

Return Values

Returns the function result, or false on error.

Examples

Example #1 forward_static_call() example

<?php

class A
{
const
NAME = 'A';
public static function
test() {
$args = func_get_args();
echo static::
NAME, " ".join(',', $args)." \n";
}
}

class
B extends A
{
const
NAME = 'B';

public static function
test() {
echo
self::NAME, "\n";
forward_static_call(array('A', 'test'), 'more', 'args');
forward_static_call( 'test', 'other', 'args');
}
}

B::test('foo');

function
test() {
$args = func_get_args();
echo
"C ".join(',', $args)." \n";
}

?>

The above example will output:

B
B more,args 
C other,args

See Also

add a note

User Contributed Notes 2 notes

up
4
arthur dot techarts at gmail dot com
13 years ago
Example to understand this function and difference with call_user_func:

<?php
class Beer {
const
NAME = 'Beer!';
public static function
printed(){
echo
'static Beer:NAME = '. static::NAME . PHP_EOL;
}
}

class
Ale extends Beer {
const
NAME = 'Ale!';
public static function
printed(){
forward_static_call(array('parent','printed'));
call_user_func(array('parent','printed'));

forward_static_call(array('Beer','printed'));
call_user_func(array('Beer','printed'));
}
}

Ale::printed();
echo
'</pre>';
?>
up
0
jhibbard at gmail dot com
12 years ago
Example usage via calls outside of the class and within an object:

<?php
/**
* @author Jonathon Hibbard
*/
class foo {
# used to verify we're actually setting something..
private static $value = '';

/**
* Simple setter for the static method setValue...
*/
public static function set($method_identifier, $value_to_pass = '') {
# make sure we have the right method format...
# another semi-useful example is like this (useful for REST-like requests...): str_replace(" ", "", ucwords(str_replace("_", " ", $method_identifier)));
$static_method = 'set' . ucfirst(strtolower(trim($method_identifier)));

if(
method_exists(__CLASS__, $static_method)) {
//Note: this will not work and will throw PHP Parse error: syntax error, unexpected '::'
//__CLASS__::$static_method($value_to_pass);

foo::$static_method($value_to_pass);

echo
"\tCalling forward_static_call with pure string and value param:\n";
forward_static_call(__CLASS__ . "::" . $static_method, $value_to_pass);

echo
"\tCalling forward_static_call with class, method array and value param:\n";
forward_static_call(array(__CLASS__, $static_method), $value_to_pass);
}
}

/**
* Set self::$value to something?
*/
public static function setValue($value_recieved = '') {
echo
"\t\tsetValue called with param of " . var_export($value_recieved, true) . "!\n";

echo
"\t\tSetting Private 'value'...\n";

self::$value = $value_recieved;

echo
"\t\tChecking the Private 'value':\n";
if(!empty(
self::$value)) {
echo
"\t\t\tPrivate 'value' was set to '" . self::$value . "' as expected!\n";
} else {
echo
"\t\t\tPrivate 'value' was not set!\n";
}

# Reset...
self::$value = '';
}

/**
* Create an object and test calling the static method from within this realm...
*/
public function __construct() {
echo
"\tCalling from within constructor..\n";
foo::set('value','Something else from within the instance!');
}
}

echo
"\n============ Calling by static method first ============\n";
foo::set('value','Something from outside of the foo class!');

echo
"\n============ Calling by static method without a value next ============\n";
foo::set('value');

echo
"\n============ Calling by createing an instance next ============\n";
new
foo();
?>
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