XML Schema any Element

The any element enables the author to extend the XML document with elements not specified by the schema.

• Parent elements: choice, sequence

<any
id=ID
maxOccurs=nonNegativeInteger|unbounded
minOccurs=nonNegativeInteger
namespace=namespace
processContents=lax|skip|strict
any attributes
>
 
(annotation?)
 
</any>

(The ? sign declares that the element can occur zero or one time inside the any element)

• id - Optional. Specifies a unique ID for the element
• maxOccurs - Optional. Specifies the maximum number of times the any element can occur in the parent element. The value can be any number >= 0, or if you want to set no limit on the maximum number, use the value “unbounded”. Default value is 1
• minOccurs - Optional. Specifies the minimum number of times the any element can occur in the parent element. The value can be any number >= 0. Default value is 1
• namespace - Optional. Specifies the namespaces containing the elements that can be used. Can be set to one of the following:
  • ##any - elements from any namespace is allowed (this is default)
  • ##other - elements from any namespace that is not the namespace of the parent element can be present
  • ##local - elements must come from no namespace
  • ##targetNamespace - elements from the namespace of the parent element can be present
  • List of {URI references of namespaces, ##targetNamespace, ##local} - elements from a space-delimited list of the namespaces can be present

• processContents - Optional. Specifies how the XML processor should handle validation against the elements specified by this any element. Can be set to one of the following:
  • strict - the XML processor must obtain the schema for the required namespaces and validate the elements (this is default)
  • lax - same as strict but; if the schema cannot be obtained, no errors will occur
  • skip - The XML processor does not attempt to validate any elements from the specified namespaces
• any attributes - Optional. Specifies any other attributes with non-schema namespace

The following example shows a declaration for an element called “person”. By using the <any> element the author can extend (after <lastname>) the content of “person” with any element:

<xs:element name="person">
  <xs:complexType>
    <xs:sequence>
      <xs:element name="firstname" type="xs:string"/>
      <xs:element name="lastname" type="xs:string"/>
      <xs:any minOccurs="0"/>
    </xs:sequence>
  </xs:complexType>
</xs:element>