php验证身份证函数

function validateIdCard($value)
{
    if (!preg_match('/^\d{17}[0-9xX]$/', $value)) { //基本格式校验
        return false;
    }

    $parsed = date_parse(substr($value, 6, 8));
    if (!(isset($parsed['warning_count']) 
        && $parsed['warning_count'] == 0)) { //年月日位校验
        return false;
    }

    $base = substr($value, 0, 17);

    $factor = [7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2];

    $tokens = ['1', '0', 'X', '9', '8', '7', '6', '5', '4', '3', '2'];

    $checkSum = 0;
    for ($i=0; $i<17; $i++) {
        $checkSum += intval(substr($base, $i, 1)) * $factor[$i];
    }

    $mod = $checkSum % 11;
    $token = $tokens[$mod];

    $lastChar = strtoupper(substr($value, 17, 1));

    return ($lastChar === $token); //最后一位校验位校验
}