XSD Syntax

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This tutorial describes:

• Simple XML Elements with Pre-defined Data Types
• Simple XML Elements with Extended Data Types
• Complex XML Elements
• Simple Content XML Elements
• Empty XML Elements
• Anomymous Data Types
• Sample XSD File - dictionary.xsd

Simple XML Elements with Pre-defined Data Types

Simple XML Element: An XML element that has no child elements and attributes. Simple XML elements can be defined in XSD with the following statement:

<xsd:element name="element_name" type="xsd:type_name"/>

where "element_name" is the name of the XML element, and "type_name" is one of the data type names pre-defined in XSD.

XSD pre-defined data types are divided into 7 groups:

• Numeric data types
• Date and time data types
• String data types
• Binary data types
• Boolean data type

Numeric data types: All commonly used integer and real number types:

• xsd:float
• xsd:double
• xsd:decimal
• xsd:integer
• xsd:nonPositiveInteger
• xsd:nonNegativeInteger
• xsd:negativeInteger
• xsd:positiveinteger
• xsd:long
• xsd:int
• xsd:short
• xsd:byte
• xsd:unsignedLong
• xsd:unsignedInt
• xsd:unsignedShort
• xsd:unsignedByte

Date and time data types: Date and time related data types. Constants of date and time types are written in the format defined by ISO 8601. For example: "2002-12-23T14:19:00.000-05:00" represents an instance of time at 14:19:00.000 on December 23, 2003, with 5:00 time zone adjustment.

• xsd:dateTime - Date and time, like "2002-12-23T14:19:00.000-05:00".
• xsd:date - Date only, like "2002-12-23".
• xsd:time - Time only, like "14:19:00.000-05:00".
• xsd:gDay - Day only, like "--23" (the 23rd day of any month of any year).
• xsd:gMonth - Month only, like "-12" (December of any year).
• xsd:gYear - Year only, like "2002".
• xsd:gYearMonth - Year and month only, like "2002-12".
• xsd:gMonthDay - Month and day only, like "-12-23".
• xsd:duration - Period of time, like "P0001Y02M03DT04H05M06.000S".

String data types: String related data types.

• xsd:string - A sequence of any Unicode characters
• xsd:normalizedString - A string with no tabs, carriage returns, or line feeds
• xsd:token - A normalized string with no any leading and trailing spaces, and no multiple consecutive spaces.

Binary data types:

• xsd:hexBinary - A sequence of hex digits to represent any binary data.
• xsd:base64Binary - Binary data written in Base64 encoding

Boolean data type:

• xsd:boolean - With 4 possible values: 0, 1, true, false.

One example of using pre-defined XSD data types is in our hello_xsd.xml:

<?xml version="1.0"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">
 <xsd:element name="p" type="xsd:string"/>
</xsd:schema>

where element "p" is defined to be a simple element type allowing child text node containing data of "xsd:string" type.

(Continued on next part...)

Part:   1   2  3