HOME

Schema Tutorial
XSD HOME
XSD Intro
XSD Why
XSD HowTo
XSD <schema>

Simple Types
XSD Elements
XSD Attributes
XSD Restrictions

Complex Types
XSD Elements
XSD Empty
XSD Elements Only
XSD Text Only
XSD Mixed
XSD Indicators
XSD <any>
XSD <anyAttribute>
XSD Substitution
XSD Example

Data Types
XSD String
XSD Date
XSD Numeric
XSD Misc

References
XSD Reference
Download XMLSpy here
Please visit our sponsors !

The element Element

Back

Definition and Usage

The element element defines an element.

Element Information

  • Parent elements: schema, choice, all, sequence, group

Syntax

<element
id=ID 
name=NCName
ref=QName
type=QName
substitutionGroup=QName
default=string
fixed=string
form=qualified|unqualified
maxOccurs=nonNegativeInteger|unbounded
minOccurs=nonNegativeInteger
nullable=true|false
abstract=true|false 
block=(#all|list of (extension|restriction))
final=(#all|list of (extension|restriction))
any attributes
>
annotation?,((simpleType|complexType)?,(unique|key|keyref)*))
</element>

(The ? sign declares that the element can occur zero or one time, and the * sign declares that the element can occur zero or more times inside the element element)

Attribute Description
id Optional. Specifies a unique ID for the element
name Optional. Specifies a name for the element. This attribute is required if the parent element is the schema element
ref Optional. Refers to the name of another element. The ref attribute can include a namespace prefix. This attribute cannot be used if the parent element is the schema element
type Optional. Specifies either the name of a built-in data type, or the name of a simpleType or complexType element
substitutionGroup Optional. Specifies the name of an element that can be substituted with this element. This attribute cannot be used if the parent element is not the schema element
default Optional. Specifies a default value for the element (can only be used if the element's content is a simple type or text only)
fixed Optional. Specifies a fixed value for the element (can only be used if the element's content is a simple type or text only)
form Optional. Specifies the form for the element. "unqualified" indicates that this attribute is not required to be qualified with the namespace prefix. "qualified" indicates that this attribute must be qualified with the namespace prefix. The default value is the value of the elementFormDefault attribute of the schema element. This attribute cannot be used if the parent element is the schema element
maxOccurs Optional. Specifies the maximum number of times this 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. This attribute cannot be used if the parent element is the schema element
minOccurs Optional. Specifies the minimum number of times this element can occur in the parent element. The value can be any number >= 0. Default value is 1. This attribute cannot be used if the parent element is the schema element
nullable Optional. Specifies whether an explicit null value can be assigned to the element. True enables an instance of the element to have the null attribute set to true. The null attribute is defined as part of the XML Schema namespace for instances. Default is false
abstract Optional. Specifies whether the element can be used in an instance document. True indicates that the element cannot appear in the instance document. Instead, another element whose substitutionGroup attribute contains the qualified name (QName) of this element must appear in this element's place. Default is false
block Optional. Prevents an element with a specified type of derivation from being used in place of this element. This value can contain #all or a list that is a subset of extension, restriction, or equivClass:
  • extension - prevents elements derived by extension
  • restriction - prevents elements derived by restriction
  • substitution - prevents elements derived by substitution
  • #all - prevents all derived elements
final Optional. Sets the default value of the final attribute on the element element.  This attribute cannot be used if the parent element is not the schema element. This value can contain #all or a list that is a subset of extension or restriction:
  • extension - prevents elements derived by extension
  • restriction - prevents elements derived by restriction
  • #all - prevents all derived elements
any attributes Optional. Specifies any other attributes with non-schema namespace

Example 1

The following example is a schema with four simple elements named "fname", "lname", "age", and "dateborn", which are of type string, nonNegativeInteger, and date:

<?xml version="1.0"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="fname" type="xs:string"/>
<xs:element name="lname" type="xs:string"/>
<xs:element name="age" type="xs:nonNegativeInteger"/>
<xs:element name="dateborn" type="xs:date"/>
</xs:schema>

Example 2

The following example is a schema with an element named "note" that is of a complex type. The "note" element contains four other simple elements; "to", "from", "heading", and "body":

<?xml version="1.0"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="note">
    <xs:complexType>
      <xs:sequence>
	<xs:element name="to" type="xs:string"/>
	<xs:element name="from" type="xs:string"/>
	<xs:element name="heading" type="xs:string"/>
	<xs:element name="body" type="xs:string"/>
      </xs:sequence>
    </xs:complexType>
</xs:element>
</xs:schema>

Example 3

This example is equal to Example 2, but here we have chosen to use the ref attribute to refer to the element names:

<?xml version="1.0"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="note">
  <xs:complexType>
    <xs:sequence>
      <xs:element ref="to"/>
      <xs:element ref="from"/>
      <xs:element ref="heading"/>
      <xs:element ref="body"/>
    </xs:sequence>
  </xs:complexType>
</xs:element>
<xs:element name="to" type="xs:string"/>
<xs:element name="from" type="xs:string"/>
<xs:element name="heading" type="xs:string"/>
<xs:element name="body" type="xs:string"/>
</xs:schema>


Back

Jump to: Top of Page or HOME or Printer Friendly Printer friendly page


Search W3Schools:


What Others Say About Us

Does the world know about us? Check out these places:

Dogpile Alta Vista MSN Google Excite Lycos Yahoo Ask Jeeves


We Help You For Free. You Can Help Us!


W3Schools is for training only. We do not warrant its correctness or its fitness for use. The risk of using it remains entirely with the user. While using this site, you agree to have read and accepted our terms of use and privacy policy.

Copyright 1999-2002 by Refsnes Data. All Rights Reserved


Validate How we converted to XHTML Validate

Domain Name Registration
Domain Name
Registration & More!



Your own Web Site?

Read W3Schools
Hosting Tutorial



$15 Domain Name
Registration
Save $20 / year!



Advertise
at W3Schools

Only 0.5 CPM



SELECTED LINKS

University Online
Master Degree
Bachelor Degree


Web Software

The Future of
Web Development


Jobs and Careers

Web Security
Web Statistics
Web Standards


PARTNERS

W3Schools
TopXML
VisualBuilder
XMLPitstop
DevelopersDex
DevGuru
Programmers Heaven
The Code Project
Tek Tips Forum
ZVON.ORG
TopXML Search