php regexp如何在子字符串后删除字符串

Question

I have problem with regex. Trying to delete a strings in text started with "(chapter 1)" constractions, but it does't work.

$line = preg_replace('/(\(chapter.*$/', '', $line);

Text for sample:

(charter 1)sample text, sample text.
(charter 2)sample text, sample text.
(charter 3)sample text, sample text.

Answer 1

$str = "(charter 1)sample text, sample text.";
$str = preg_replace("#^\(charter \d*\)#", "", $str);

// output: sample text, sample text.