# call_user_func

(PHP 4, PHP 5)

call_user_func — Call a user function given by the first parameter

### Description

mixed call_user_func ( callback `$function` [, mixed `$parameter` [, mixed `$...` ]] )

Call a user defined function given by the `function` parameter.

### Parameters

`function`

  The function to be called. Class methods may also be invoked statically using this function by passing array($classname, $methodname) to this parameter.

`parameter`

  Zero or more parameters to be passed to the function.

  > Note: Note that the parameters for call_user_func() are not passed by reference.

  > `<?php
  > function increment(&$var)
  > {
  > $var++;
  > }
  > $a = 0;
  > call_user_func('increment', $a);
  > echo $a; // 0
  > call_user_func_array('increment', array(&$a)); // You can use this instead
  > echo $a; // 1
  > ?>`

### Return Values

Returns the function result, or `FALSE` on error.

### Examples

Example#1 call_user_func() example

`<?php
function barber($type)
{
echo "You wanted a $type haircut, no problem";
}
call_user_func('barber', "mushroom");
call_user_func('barber', "shave");
?>`

Example#2 Using a class method

`<?php
class myclass {
function say_hello()
{
echo "Hello!\n";
}
}
$classname = "myclass";
call_user_func(array($classname, 'say_hello'));
?>`

### See Also

- call_user_func_array()
- is_callable()
- information about the callback type