"Hello world!" Example of XSD

∟"Hello world!" Example of XSD

This section describes a simple example of XSD called 'Hello World'.

Before getting into details of XSD specifications, let's look at a simple example of an XML schema defined in XSD language, hello.xsd:

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

Note that:

This XSD file is a true XML document with the root element named as "schema".
This XSD file contains one single "Element Declaration" statement <element ...>.
The "Element Declaration" statement declares that the conforming XML documents must have a root element named as "p".
The "Element Declaration" statement also declares that the root element "p" should have content of XSD "string" type.

Obviously, hello.xsd is a very simple XML schema. Writing an XML document that conforms to hello.xsd is easy. There is an example, hello.xml

<?xml version="1.0"?>
<p>Hello world!</p>

Let's validate hello.xml against hello.xsd manually:

hello.xml has a root element of "p" which matches the name declared in hello.xsd.
The content of "p" is a string, "Hello world!", which matches the datatype declared in hello.xsd.