C# 5.0 Unleashed

Expression Trees

In the C# 3.0 era, coinciding with the .NET Framework 3.5 release, the mission to solve the impedance mismatch between object-oriented programming and various data models required the ability to represent code as data. In Chapter 20, “Language Integrated Query Internals,” you saw how LINQ query expressions translate into chains of query operator method calls. For query providers to be able to make sense of the querying intent specified by the user, all information captured in the invocations of query operators needs to be available in an object model at runtime. To solve this problem, expression trees were introduced.

We now take a look at two sides spanned by expression trees. One is the generation of expression trees by the ...