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XML Schema group Element

Definition and Usage

The group element is used to define a group of elements to be used in complex type definitions.

Element Information

Parent elements: schema, choice, sequence, complexType, restriction (both simpleContent and complexContent), extension (both simpleContent and complexContent)

Syntax

<group
id=ID
name=NCName
ref=QName
maxOccurs=nonNegativeInteger|unbounded
minOccurs=nonNegativeInteger
any attributes
>

(annotation?,(all|choice|sequence)?)

</group>

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

Attribute	Description
id	Optional. Specifies a unique ID for the element
name	Optional. Specifies a name for the group. This attribute is used only when the schema element is the parent of this group element. Name and ref attributes cannot both be present
ref	Optional. Refers to the name of another group. Name and ref attributes cannot both be present
maxOccurs	Optional. Specifies the maximum number of times the group 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 group element can occur in the parent element. The value can be any number >= 0. Default value is 1
any attributes	Optional. Specifies any other attributes with non-schema namespace

Example 1

The following example defines a group containing a sequence of four elements and uses the group element in a complex type definition:

<?xml version="1.0"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">

<xs:group name="custGroup">
  <xs:sequence>
    <xs:element name="customer" type="xs:string"/>
    <xs:element name="orderdetails" type="xs:string"/>
    <xs:element name="billto" type="xs:string"/>
    <xs:element name="shipto" type="xs:string"/>
  </xs:sequence>
</xs:group>

<xs:element name="order" type="ordertype"/>

<xs:complexType name="ordertype">
  <xs:group ref="custGroup"/>
  <xs:attribute name="status" type="xs:string"/>
</xs:complexType>

</xs:schema>

Complete XML Schema Reference