创建一个variable_function作为类的成员

Question

Let's say we have a class stockFns and I do

$stockFns->{$functionOne}=create_function('$a,$b' , 'return $a+$b;');

This creates a property in $stockFns named whatever create_function returned.

Now I want to refer (invoke) to the created_function.

What would be a clean way to do it in a single instruction?. An example

$stockFns=new StockFns;
$functionOne='add';
$stockFns->{$functionOne}=create_function('$a,$b' , 'return $a+$b;');

//echo "***" . ($stockFns->add)(1,2);  // That doesn't work
$theFn=$stockFns->add;
echo $theFn(1,2);         // This works but reuires two instructions

Thanks!

Answer 1

Either your way, or

echo call_user_func(array($stockFbs, 'add'), 1, 2);

The problem is, that PHP cannot distinguish real methods from properties with callables. If you call something with () it will not touch the properties at all and in maybe will call __call, if it exists. You can try something like

class StockFns {
  public function __call ($name, $args) {
    $fctn = $this->{$name};
    return call_user_func_array($fctn, $args);
  }
}

As a workaround, so __call() will redirect to your callback.