How to remove lines from textarea 1 which not contains each lines in textarea 2 ? [PHP]

Question

Example

Textarea 1:

A123
B456
C789
D012

Textarea 2:

123
789

And when click button will show this result:

A123
C789

Answer 1

You can do something like below,

$data = ["A123","B456"];
$data1 = ["123"];
$newArr = array();
foreach($data1 as $val) {
    foreach($data as $fVal) {
        if(stristr($fVal,$val)) {
            $newArr[] = $fVal;
        }
    }
}

print "<pre>"; print_r($newArr);