手机号加密

/**
 * 中间加密 字符串截取法
 */
  function encryptTel1($tel1) {
    $new_tel = substr($tel, 0, 3).'****'.substr($tel, 7);
    return $new_tel;
}
/**
 * 中间加密 替换字符串的子串
 */
  function encryptTel2($tel2) {
    $new_tel = substr_replace($tel, '****', 3, 4);
    return $new_tel;
}  
/**
 * 中间加密 用正则
 */
  function encryptTel3($tel3) {
    $new_tel = preg_replace('/(\d{3})\d{4}(\d{4})/', '****', $tel);
    return $new_tel;
}

echo encryptTel3(15039378786);

js手机号加密

 　　　　let val = 15039378786;
        let phone = String(val);
        let reg = /(\d{3})\d{4}(\d{4})/;
        console.log(phone.replace(reg, '$1****$2')) ;