1. public function blur_number($string)
    2.     {
    3.         if (SimpleValidator::email($string)) {
    4.             $head = substr($string, 0, 1);
    5.             $tail = substr($string, strpos($string, '@'));
    7.             return $head.'***'.$tail;
    8.         } elseif (SimpleValidator::mobile($string)) {
    9.             $head = substr($string, 0, 3);
    10.             $tail = substr($string, -4, 4);
    12.             return $head.'****'.$tail;
    13.         } elseif (SimpleValidator::bankCardId($string)) {
    14.             $tail = substr($string, -4, 4);
    16.             return '**** **** **** '.$tail;
    17.         } elseif (SimpleValidator::idcard($string)) {
    18.             $head = substr($string, 0, 4);
    19.             $tail = substr($string, -2, 2);
    21.             return $head.'************'.$tail;
    22.         }
    23.     }