XML Validation
“Well Formed” XML documents
A “Well Formed” XML document is a document that conforms to the XML syntax rules that we described in the previous chapter.
The following is a “Well Formed” XML document:
<?xml version="1.0"?> <note> <to>Tove</to> <from>Jani</from> <heading>Reminder</heading> <body>Don't forget me this weekend!</body> </note> |
“Valid” XML documents
A “Valid” XML document is a “Well Formed” XML document which conforms to the rules of a Document Type Definition (DTD).
The following is the same document as above but with an added reference to a DTD:
<?xml version="1.0"?> <!DOCTYPE note SYSTEM "InternalNote.dtd"> <note> <to>Tove</to> <from>Jani</from> <heading>Reminder</heading> <body>Don't forget me this weekend!</body> </note> |
More about XML DTD
You can read more about DTD in the chapter XML DTD.