declaring and calling PHP object functions with period in name - php

Question

I'm using an API that returns different values, and I want to dynamically tell my class to run a function with the same name (so i won't need a huge switch or if/else mess).
How can I declare the object method song.pause?
How can I use the object method song.pause?
This might be an XY Problem, so is there a better way to do this? One alternative i thought of is to always call str_replace('.','_',$type) and set functions without the periods. Thoughts?
Example:
<?php
class MyClass {
...
...
$type = "song.pause"; // This value is returned from another API I can't control
if (property_exists('MyClass', $type)) {
$success = $this->{$type}(); // ???
} else {
header("HTTP/1.1 400 Invalid type: $type);
exit;
}
public function 'song.pause'() { // obviously incorrect :)
???
}

Answer 1

Given a return of song.pause, conceptually song should be the class name and pause should be the method, consider this possibility:
class MyClass {
protected $classes = array();
function processResponse($response) {
// $response example is "song.pause"
list($class, $method) = explode('.', $response);
if(!class_exists($class)) {
// Class doesn't exist
die("Class name {$class} doesn't exist! Exiting...");
}
// Instantiate class
$this->classes[$class] = new $class();
if(!method_exists($this->classes[$class], $method)) {
// Method doesn't exist within specified class
die("Method name {$method} doesn't exist within {$class}. Exiting...");
}
// Call method
$result = $this->classes[$class]->{$method}();
return $result;
}
}
Your logic implementation would be something like this:
class song {
public function pause() {
return 'foobar';
}
}
Here's an example.

Answer 2

Unfortunately, what you're generally asking is not supported. From the manual:
Function names follow the same rules as other labels in PHP. A valid
function name starts with a letter or underscore, followed by any
number of letters, numbers, or underscores. As a regular expression,
it would be expressed thus: [a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*.
This also applies to class methods.
As the walkaround, you may follow the way that you suggested yourself:
$type = 'song.pause';
$type = str_replace('.', '_', $type);
$this->{$type}(); // will call song_pause()
OR use "dark" magic:
<?php
// header('Content-Type: text/plain; charset=utf-8');
class Test {
function __call($method, $args){
// do redirect to proper processing method here
print_r($method);
echo PHP_EOL;
print_r($args);
}
}
$x = new Test();
$x->{'song.pause'}(1,2,3);
?>
Shows:
song.pause // < the method
Array // < arguments
(
[0] => 1
[1] => 2
[2] => 3
)
However, the "long" and really transparent way, which I completely agree with, is suggested by #scrowler.

Answer 3

#HAL9000 is right: what you want is not supported. One potential workaround is:
Define the handlers:
$typeHandlers = array();
$typeHandlers['song.pause'] = function () {
echo 'Pause!'; // or whatever...
};
Call the appropriate handler:
$typeHandlers[$type]();