Professional C# 2005

Chapter 11. Reflection

Reflection is a generic term that describes the ability to inspect and manipulate program elements at runtime. For example, reflection allows you to:

• Enumerate the members of a type

• Instantiate a new object

• Execute the members of an object

• Find out information about a type

• Find out information about an assembly

• Inspect the custom attributes applied to a type

• Create and compile a new assembly

This list represents a great deal of functionality and encompasses some of the most powerful and complex capabilities provided by the .NET Framework class library. Unfortunately, this chapter does not have the space to cover all the capabilities of reflection and so it focuses on those elements you are likely to use frequently.

The discussion begins with custom attributes, a mechanism that allows you to associate custom metadata with program elements. This metadata is created at compile time and embedded in an assembly. You can then inspect the metadata at runtime using some of the capabilities of reflection.

After looking at custom attributes, the chapter looks at some of the fundamental classes that enable reflection, including the System.Type and System.Reflection.Assembly classes, which provide the access points for much of what you can do with reflection.

To demonstrate custom attributes and reflection, you develop an example based on a company that regularly ships upgrades to its software, and wants to have details of these upgrades documented automatically. In the example, ...