DTD questions

[Elizabeth King]

Hi
Are the following DTD definitions for an
element <book> correct? I think both are correct.
A) <!ELEMENT title #PCDATA>
<!ELEMENT author #PCDATA>
<!ELEMENT book (#PCDATA, title, author)>
B> <!ELEMENT title #PCDATA>
<!ELEMENT author #PCDATA>
<!ELEMENT book (#PCDATA, title, #PCDATA, author, #PCDATA)>
Thanks.

[Rakesh Gudur]

Hai Mary,
Both of them are incorrect. The DTD should be something like
<!ELEMENT author (#PCDATA)>
<!ELEMENT title (#PCDATA)>
<!ELEMENT book (#PCDATA | author | title)*>
When I put the other ones in XML Spy, it gives an error. The above one is correct. Hope this helps.
Rakesh.

[Luciano Queiroz]

In addition, I would like to remind you of a little detail.
In a DTD, when you declare a mixed element, the #PCDATA child must be the first sub-element inside the parenthesis.
Ex.:
<!ELEMENT house (#PCDATA, door, window)>

[Dan Drillich]

The only two ways PCDATA can be used are -
by itself -
<!ELEMENT house (#PCDATA)>
or in a mixed content model -
<!ELEMENT house (#PCDATA | door | window)*>
Cheers,
Dan

[Jerry Sheehan]

Why are you still writing DTD's anyway? XSD schemas are much more powerful and if you already have existing DTD's, you can use XMLSpy to convert it to a W3C compliant XSD.