XML and ASP.NET

Over the years , the MSXML component has grown to provide more functionality than just parsing. With the release of MSXML 4.0, the original name MSXML Parser has been changed to Microsoft XML Core Services. The following features and changes in MSXML 4.0 are new compared to MSXML 3.0:

• Extended support for the final W3C XML Schema (XSD) Recommendation ” Earlier versions of MSXML used the XML data-reduced schema language.Version 4.0 supports validation against W3C XSD schemas (proposed recommendation: March 30, 2001). It's possible to activate XSD validation by using the schemaLocation attribute instead of loading a schema independently and setting it to use a schema cache. Schema type information is accessible in DOM by using additional Schema Object Model (SOM) APIs.

• Extended support for SAX ” You can use the MXXMLWriter object to generate SAX events out of a DOM tree and, likewise, build a DOM tree out of SAX events. A new object, MXHTMLWriter , enables you to output HTML using a stream of SAX events. It is possible to track namespace declarations through a newly added IMXNamespaceManager interface. A SaxAppWizard utility for Microsoft Visual Studio simplifies C++-based SAX components ' development.

• SAX-based XSD validation and type discovery ” Support for XSD validation using the SAX parser is added through the IMXSchemaDeclHandler extension handler interface according to the SAX2 standard.

• New and faster parser ” By setting the NewParser property to True, you can use the new and faster XML parser.

• Removal of Replace mode ” Until MSXML 3.0, you could use Replace mode to make the latest MSXML component simulate MSXML 2.0. But this feature has been completely removed from MSXML 4.0 to avoid the application-maintenance problems. For the same reason, the version-independent ProgIDs were removed. You must use the version-dependent ProgID MSXML2.DOM Document.4.0 to instantiate the MSXML 4.0 parser.

• Removal of legacy code ” The Replace mode was intended to support old code while using the newer version of the parser. This made the size of the MSXML component much bigger than it would have normally been. Some of the legacy features that were removed include the old non-conformant XSL (in favor of XSLT 1.0), XSLPattern language ( replaced by XPath 1.0), and XDR rudimentary uuid: namespaces.

• Separate WinHTTP Version 5.0 component ” Functionality of the ServerHTTPRequest component is now provided by a separate WinHTTP 5.0 component, which is shipped and installed with MSXML 4.0. This is a new server-side component that provides reliable HTTP stack functionality.

• Faster XSLT engine ” An XSLT engine that is at least 4 times faster except for a known serious performance bug with the xsl:key.