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XML Schema sequence Element

Definition and Usage

The sequence element specifies that the child elements must appear in a sequence. Each child element can occur from 0 to any number of times.

Element Information

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

Syntax

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

Attribute	Description
id	Optional. Specifies a unique ID for the element
maxOccurs	Optional. Specifies the maximum number of times the sequence 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 sequence 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

This example shows a declaration for an element called "personinfo", which must contain the following five elements in order; "firstname", "lastname", "address", "city", and "country":

<xs:element name="personinfo">
  <xs:complexType>
    <xs:sequence>
      <xs:element name="firstname" type="xs:string"/>
      <xs:element name="lastname" type="xs:string"/>
      <xs:element name="address" type="xs:string"/>
      <xs:element name="city" type="xs:string"/>
      <xs:element name="country" type="xs:string"/>
    </xs:sequence>
  </xs:complexType>
</xs:element>

Example 2

This example shows a declaration for an element called "pets" that can have zero or more of the following elements, dog and cat, in the sequence element:

<xs:element name="pets">
  <xs:complexType>
    <xs:sequence minOccurs="0" maxOccurs="unbounded">
      <xs:element name="dog" type="xs:string"/>
      <xs:element name="cat" type="xs:string"/>
    </xs:sequence>
  </xs:complexType>
</xs:element>

Complete XML Schema Reference