验证身份证

$id = $_REQUEST;
isIdcard($id['id']);
function isIdcard($id){
    if(!empty($id)){
        $id = strtoupper($id);
        $regx = "/(^d{15}$)|(^d{17}([0-9]|X)$)/";

        $arr_split = [];
        if(!preg_match($regx, $id)){
            echo "身份证识别错误";
            //return false;
        }

        if(15==strlen($id)){
            // 检查15位
            echo 123;
            $regx = "/^(d{6})+(d{2})+(d{2})+(d{2})+(d{3})$/";

            @preg_match($regx, $id, $arr_split);
            // 检查生日日期是否正确
            $dtm_birth = "19" . $arr_split[2] . '/' . $arr_split[3] . '/' . $arr_split[4];

            if(!strtotime($dtm_birth)){
                echo "身份证识别错误";
                return false;
            }else{
                echo "yes";
                //return true;
            }
        }else{
            // 检查18位
            $regx = "/^(d{6})+(d{4})+(d{2})+(d{2})+(d{3})([0-9]|X)$/";
            @preg_match($regx, $id, $arr_split);

            $dtm_birth = $arr_split[2] . '/' . $arr_split[3] . '/' . $arr_split[4];

            //检查生日日期是否正确
            if(!strtotime($dtm_birth)) {
                echo "身份证识别错误";
                return false;
            }else{

                //检验18位身份证的校验码是否正确。
                //校验位按照ISO 7064:1983.MOD 11-2的规定生成，X可以认为是数字10。
                $arr_int = [7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2];
                $arr_ch = ['1', '0', 'X', '9', '8', '7', '6', '5', '4', '3', '2'];
                $sign = 0;

                for ( $i = 0; $i < 17; $i++ ){
                    $b = (int) $id{$i};
                    $w = $arr_int[$i];
                    $sign += $b * $w;
                }
                $n = $sign % 11;
                $val_num = $arr_ch[$n];

                if ($val_num != substr($id,17, 1)){
                    echo "身份证识别错误";
                    return false;
                }else{
                    return true;
                }
            }
        }
    }



}