XML Schema Issue

PatrickNew · 01-08-2009, 02:17 PM

Okay, so I finished the w3schools tutorial on XML Schema, and I still have a question about something. I'm trying to do something like type inheritance. I think a quick example would demonstrate this well:

Code:

<scope>
  <var_decl/>
  <var_decl/>
  <conditional />
  <loop />
</scope>

The idea is that scope should be able to contain an ordered list of statements, where a var_decl is a statement, a condition is a statement, and a loop is a statement.

Relevant XSD snippets of my current attempts are included below:

Code:

<xs:complexType name="statement">
  <xs:choice>
    <xs:element ref="var_decl"/>
    <xs:element ref="conditional"/>
    <xs:element ref="loop"/>
  </xs:choice>
</xs:complexType>

But this doesn't really do what I want. This defines the type 'statement' to be an element that contains a var_decl, conditional, or loop. I want it to define a type that IS either a var_decl, conditional, or loop.

Any ideas?

paulsm4 · 01-10-2009, 01:41 AM

Hi -

Here's a link that discusses what you're trying to do:

ftp://ftp.computer.org/press/outgoin...hipala-xml.pdf

Code:

<xs:complexType name="EmployeeType">
  <xs:sequence>
    <xs:element name="id" type="xs:string"/>
    <xs:element name="name" type="xs:string"/>
    <xs:element name="gender" type="xs:string"/>
  </xs:sequence>
</xs:complexType>

Code:

<xs:complexType name="PermanentEmployeeType">
  <xs:complexContent>
    <xs:extension base="EmployeeType">
      <xs:sequence>
        <xs:element name="salary" type="xs:string"/>
      </xs:sequence>
    </xs:extension>
  </xs:complexContent>
</xs:complexType>

'Hope that helps .. PSM

PatrickNew · 01-12-2009, 09:29 AM

That helps a lot. Thanks man!