If you want to validate an XML document against a DTD that is not referenced by the document itself, you can use the keyword argument to parse from a file.
This also enables correct handling of include files from within the Relax NG parser.
The Validation Type property of the Xml Reader Settings object is set to to enforce validation of the XML document by the Create method of the Xml Reader object.
A Validation Event Handler is added to the Xml Reader Settings object to handle any Warning or Error events raised by errors found during the validation process of both the XML document and the schema.
To validate an XML document, construct an Xml Reader Settings object that contains an XML schema definition language (XSD) schema with which to validate the XML document. For more information on validating XML documents with LINQ to XML, see How to: Validate Using XSD. Validation Event Handler, New Validation Event Handler(Address Of books Settings Validation Event Handler) Dim books As Xml Reader = Xml Reader. Read() End While End Sub Shared Sub books Settings Validation Event Handler(By Val sender As Object, By Val e As Validation Event Args) If e.
An individual schema or a set of schemas (as an Xml Schema Set) can be added to an Xml Schema Set by passing either one as a parameter to the Add method of Xml Schema Set.
These are the same constants you define when using XML Schema for SAX parsing, and they are declared at the beginning of the Because JAXP-compliant parsers are not namespace-aware by default, it is necessary to set the property for schema validation to work.
Now that the program is ready to validate with an XML Schema definition, it is necessary only to ensure that the XML document is associated with (at least) one.
There are two ways to do that: , which stands for "XML Schema instance." The second line specifies the schema to use for elements in the document that do not have a namespace prefix-that is, for the elements you typically define in any simple, uncomplicated XML document.
Apart from the built-in DTD support in parsers, lxml currently supports three schema languages: DTD, Relax NG and XML Schema.
All three provide identical APIs in lxml, represented by validator classes with the obvious names.