Question

我已尝试使用1-2个验证器来验证此DTD，但我不确定它为何无效：

DTD代码：

任何帮助将不胜感激！

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE cars 
[
    <!ELEMENT car (maker, model, year, colour, engine, number_of_doors, accessories)>

    <!ELEMENT maker (#PCDATA)>
    <!ELEMENT model (#PCDATA)>
    <!ELEMENT year (#PCDATA)>
    <!ELEMENT colour (#PCDATA)>
    <!ELEMENT engine (number_of_cylinders)>
    <!ELEMENT number_of_doors (#PCDATA)>
    <!ELEMENT accessories (#PCDATA)>

    <!ELEMENT number_of_cylinders (#PCDATA)>

    <!ATTLIST accessories radio (yes|no) #REQUIRED
        air_conditioning (yes|no) #REQUIRED
        power_windows (yes|no) #REQUIRED
        power_steering (yes|no) #REQUIRED
        power_brakes (yes|no) #REQUIRED
    >
]>

Answer 1

要使具有内部DTD子集的XML文档有效，请进行以下更改：

将文档元素从cars更改为car。

构建与给定内部子集关联的XML。

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE car 
[
<!ELEMENT car (maker, model, year, colour, engine, number_of_doors, accessories)>

<!ELEMENT maker (#PCDATA)>
<!ELEMENT model (#PCDATA)>
<!ELEMENT year (#PCDATA)>
<!ELEMENT colour (#PCDATA)>
<!ELEMENT engine (number_of_cylinders)>
<!ELEMENT number_of_doors (#PCDATA)>
<!ELEMENT accessories (#PCDATA)>

<!ELEMENT number_of_cylinders (#PCDATA)>

<!ATTLIST accessories radio (yes|no) #REQUIRED
    air_conditioning (yes|no) #REQUIRED
    power_windows (yes|no) #REQUIRED
    power_steering (yes|no) #REQUIRED
    power_brakes (yes|no) #REQUIRED>
]>
<car>
    <!-- Finish building out the XML per the internal subset. -->
</car>

Answer 2

您可以使用此验证器最适合DTD https://validator.w3.org/check

为什么这个DTD无效？

2 个答案: