如何在php中检测字符串中的Json

I am stuck in a problem that I have a string which has a complete description as well as a json containing some Ids. How can I take the Json out the String and perform any event on it..

My data looks like following

The description of xxxxxxxxxxxxxxxxxxxxxxxxxx
[{"id":"613"},{"id":"614"},{"id":"615"}]

Is there any way that I can have the Complete Description and also have the IDs so that I can decode them and use where I want?

Thank you in advance for the support

try this

$string = 'The description of xxxxxxxxxxxxxxxxxxxxxxxxxx    [{"id":"613"},{"id":"614"},{"id":"615"}] asdasd';

if(false !== preg_match('/\[(.*)\]/', $string, $matches)) {
    for($n = 1; $n < count($matches); $n++) {
        $json_result = json_decode('['.$matches[$n].']', true);
        if(null === $json_result) {
            //cannot parse json
        }
        print_r($json_result);
    }
}

This will find the first LINE which has JSON code if your json is in new line !!!

$string = 'The description of xxxxxxxxxxxxxxxxxxxxxxxxxx
[{"id":"613"},{"id":"614"},{"id":"615"}]';
$strings = explode("
",$string);

foreach($strings as $str){
    $json = json_decode($str,TRUE); //TRUE for array responde
    if(!empty($json)){
       break;
    }
}

var_dump($json);