New Features in C# 3.0

Almost two years ago — before Visual Studio 2005 and C# 2.0 even shipped — Microsoft announced features that would be in C# 3.0. In May of 2006, they released a preview version of Visual Studio, called "Orcas," which contained early versions of C# 3.0, some Visual Basic language enhancements, and other new features. Microsoft also released the C# 3.0 Language Specification, which details the new language features.

The stated intent of the new language features is "to support the creation and use of higher-order, functional-style class libraries." To that end, the following features are introduced:

• Implicitly typed local variables.
• Object initializers.
• Collection initializers.
• Anonymous types.
• Implicitly typed arrays.
• Extension methods.
• Lambda expressions.
• Query expressions.
• Expression trees.