Learn XSD Schemas .NET Tutorial

In real world applications, manually creating classes for each XML type your application handles can be a tedious job, especially when you are dealing with very large schemas. Luckily, we don’t have to create the classes by hand when we have an XML schema describing the data format. The .NET Framework supplies a command line tool called XML Schema Definition Tool (xsd.exe) to produce C#, VB.NET or JScript classes for types defined in XSD schemas and vice versa. The tool will also perform a number of other XML related conversions that come handy during development work. Table C.1 lists the different options and their invocation syntax.

Let’s think about this for a moment before we continue to explore the functionality of the XML Schema definition tool. You can take any .NET assembly – your own as well as third party – and extract the type information into an XSD schema. That is something that was not possible before on the Microsoft platform. Before .NET, native Win32 DLLs and EXEs only contained the executable code and binary data structures. COM type-libraries contained some metadata about classes and their interfaces, but developers had to create them explicitly. .NET assemblies on the other hand contain complete metadata about all classes inside: class names, function names, parameter names, types of local variables, everything. The .NET Framework exposes this metadata to developers through the classes in the System.Reflection namespace. The XSD tool uses these classes to analyze assemblies and then creates schemas with the classes in System.Xml.Schema. All other conversions are also done entirely using classes provided by the .NET Framework. The XSD command-line application itself only “glues” these classes together.