The dynamic
keyword declares a variable whose type is not known at compile time. A dynamic
variable can contain any value, and the type of the value can change during runtime.
As noted in the book "Metaprogramming in .NET", C# does not have a backing type for the dynamic
keyword:
The functionality enabled by the
dynamic
keyword is a clever set of compiler actions that emit and useCallSite
objects in the site container of the local execution scope. The compiler manages what programmers perceive as dynamic object references through thoseCallSite
instances. The parameters, return types, fields, and properties that get dynamic treatment at compile time may be marked with some metadata to indicate that they were generated for dynamic use, but the underlying data type for them will always beSystem.Object
.