Name

xs:element

Synopsis

<xs:element

  abstract = "( true | false )"
  block = "( #all | extension | restriction | substitution )"
  default = "string"
  final = "( #all | extension | restriction )"
  fixed = "string"
  form = "( qualified | unqualified )"
  id = "ID"
  maxOccurs = "( nonNegativeInteger | unbounded )"
  minOccurs = "nonNegativeInteger"
  name = "NCName"
  nillable = "( true | false )"
  ref = "QName"
  substitutionGroup = "QName"
  type = "QName">
  <!-- ( xs:annotation?,
       ((xs:simpleType | xs:complexType)?,
       (xs:unique | xs:key | xs:keyref)*) ) -->
</xs:element>

The xs:element element declares an element, including its name and type. Used at the top level of the schema, it indicates a potential root element. Used inside an xs:complexType element, it indicates a potential child element of another element. Alternately, instead of specifying a name and a type, it can have a ref attribute that points to a top-level element declaration elsewhere in the schema.

Attributes

abstract, optional

If the abstract attribute has the value true, then only elements from this element's substitution group are allowed in instance documents, not elements actually declared by this declaration.

default, optional

default is the default value of the element reported for empty elements matching this declaration in the instance document.

block, optional

If the block attribute contains the value extension or restriction, then this element cannot be replaced in instance documents by instances of subtypes derived from this element's type by extension or restriction, respectively. If the block attribute has the value substitution, then this element cannot be replaced in instance documents by members of this element's substitution group. If the block attribute has the value #all, then this element cannot be replaced in instance documents by subtype instances or substitution group members.

final, optional

The final attribute controls which elements can refer to this element as the head of their substitution group. If the value contains the keyword restriction, then restrictions of this element's type cannot do so. If the value contains the keyword extension, then extensions of this element's type cannot do so. If the value is #all, then neither extensions nor restrictions of this type can do so.

fixed, optional

If the fixed attribute is present, then the only legal value for this element's content is the value of the fixed attribute. Only elements with simple types may be fixed.

form, optional

If the form attribute has the value qualified, then the element is in the schema's target namespace. If it has the value unqualified, then the element is not in any namespace. The default value is set by the elementFormDefault attribute on the root xs:schema element. This attribute can only be used on locally declared elements. All globally declared elements are always in the schema's target namespace.

id, optional

id is an XML name unique within ID-type attributes in this schema document.

maxOccurs, optional

This signifies the maximum number of times this element may be repeated in valid instance documents.

minOccurs, optional

This signifies the minimum number of times this element must be repeated in valid instance documents.

name, optional

This contains the required name of the element. If this is omitted, the xs:element should be empty and must have a ref attribute that points to another element declaration.

nillable, optional

If nillable has the value true, then this element can be specified as being "nil" using an xsi:nil="true" attribute in the instance document.

ref, optional

The qualified name of an element declared by a top-level xs:element element.

substitutionGroup, optional

This is the qualified name of a globally declared element for which this element may substitute in instance documents.

type, optional

This is the qualified name of the type of the element, either a built-in simple type such as xs:integer, xs:anyType, or a user-defined type.

Contents

The xs:element element may contain an optional xs:annotation. If and only if the xs:element element does not have a type attribute, then it must have either an xs:simpleType child element or an xs:complexType child element that provides an anonymous type for this element. Finally, it may have any number of xs:key, xs:keyref, and xs:unique elements that set uniqueness and identity constraints.