PHP：使用变量方法链接方法

Question

Here is my code:

return PDF::loadFile($url)
    ->setPaper('a4')
    ->setOption('margin-top', 10)
    ->stream('somefile.pdf');

As I am calling this method on multiple locations, is there some kind of option to call it in a way like this?

return PDF::loadFile($url)
    ->callSettings()
    ->stream('somefile.pdf');

Where the settings are ->setPaper('a4')->setOption('margin-top', 10).

Answer 1

It's easy. Just implement a new callSettings() method in PDF class, that calls those methods and returns $this:

public function callSettings()
{
    $this->setPaper('a4')
         ->setOption('margin-top', 10);

    return $this;
}