[UziTech]

is there a way to write a schema so an attribute is required only if there is multiple elements?

Valid XML examples:

<root>
  <elem name="x"/>
</root>

<root>
  <elem name="x" option="1" />
  <elem name="x" option="2" />
</root>

Invalid XML examples:

<root>
  <elem name="x" option="1" />
</root>

<root>
  <elem name="x" />
  <elem name="x" />
</root>

[mojo666]

I think you can accomplish this with a xs:choice

[UziTech]

mojo666, on 31 July 2012 - 11:45 AM, said:

I think you can accomplish this with a xs:choice

I tried this:

<?xml version="1.0" encoding="utf-8"?>
<xs:schema id="xml" elementFormDefault="qualified" xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xs:element name="root">
    <xs:complexType>
      <xs:choice>
        <xs:element name="elem" minOccurs="0" maxOccurs="1">
          <xs:complexType>
            <xs:attribute name="name" type="xs:string" use="required"/>
          </xs:complexType>
        </xs:element>
        <xs:element name="elem" minOccurs="2" maxOccurs="unbounded">
          <xs:complexType>
            <xs:attribute name="option" type="xs:string" use="required"/>
            <xs:attribute name="name" type="xs:string" use="required"/>
          </xs:complexType>
        </xs:element>
      </xs:choice>
    </xs:complexType>
  </xs:element>
</xs:schema>

but it says the element names to choose from are ambiguous because the choice is between elem and elem it doesn't look at any other attributes.