PHP在[[]]括号内获取字符串到数组

I am writing some snippet script with PHP,

I have these kind of string variable

 $msg="Dear [[5]]
    We wish to continue the lesson with the [[6]]";

i need to grab 5 and 6 from this $msg and assign to an array ex array(5,6)

because those are the snippets numbers, any one know how to do that using PHP

thank you for help

Use preg_match_all:

$msg = "Dear [[5]] We wish to continue the lesson with the [[6]]";
preg_match_all("/\[\[(\d+)\]\]/", $msg, $matches);

If there is a match, $matches[1] will then contain an array with the matched numbers:

Array
(
    [0] => 5
    [1] => 6
)

DEMO.

Here is what you want:

<?php

$msg = "Dear [[5]]
 We wish to continue the lesson with the [[6]]";

preg_match_all('/\[\[([0-9+])\]\]/', $msg, $array);

$array = $array[1];

print_r($array);

?>

Output:

Array
(
    [0] => 5
    [1] => 6
)