.NET & XML

When to Use W3C XML Schema

You should probably create XML Schema for your XML documents if any of the following apply:

• The order and number of nodes in your document must be constrained.

• The data within your document’s nodes must be constrained more specifically than a DTD allows.

• You wish to generate code to read and write XML to and from .NET types or a relational database using XmlSerializer or XmlDataDocument.

Conversely, you should strongly consider sticking with validation by DTD only if all of the following apply:

• Nodes may appear in your XML document in any order and number.

• The data in your document’s nodes may be free-form, and need not be constrained.

• You will be reading and writing data to and from XML documents only using XmlReader, XmlWriter, XmlDocument, XPathDocument, and the other built-in .NET XML types.