The Metaspec C# parser is fully compliant with ECMA-334 and ECMA-335 standards. In addition, it supports Microsoft-specific extensions. For details about the C# parser library, see the online documentation (C# edition or C++ edition).

C# 3.0 supported features:

- new C# 3.0 type inference algorithm
- implicitly typed local variables
- object initializers
- collection initializers
- anonymous object creation expressions
- lambda expressions
- anonymous types
- extension methods
- query expressions
- partial methods

C# 2.0 supported features:

- generics
- nullable types
- anonymous methods