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.NET reflection

Forum .NET 3rd Meeting ● February 15, 2006

By Damián Laufer

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Agenda

What is reflection Getting metadata Object creation / use Embedded resources Performance issues Security (!) Tools

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What is Reflection?

- A set of classes that allow you to access and manipulate assemblies and modules, and the types and the metadata that they contain.

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Getting metadata

- Get metadata from an assembly- AssemblyName- Modules- Types (classes, interfaces, value types,

enumeration types)- Members (constructors, methods,

properties, fields, events)- Parameters

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(classes, interfaces, value types, enumeration types)

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Object creation

- Load assemblies dynamically- Create classes- Call members- Get events

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Loading assemblies / types

Assemblies Asm = Assembly.GetExecutingAssembly Asm = Assembly.LoadFrom(“path”) Asm = Assembly.load(“mscorlib”)

Types Ty = asm.GetType(“Name”) Ty = GetType(String) Ty = anInstance.GetType Ty = Type.GetType(“System.Int32”)

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Embedded resources

- Bitmaps- Icons- Cursors- Audio files- Video files- String tables

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Performance issues

- Slower (muuuuuuch slower)

- So, why should you use it?- Task manager- Data bound list view control- data row<-->class loader (CRUD)

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Security – hang on!

- Getting private metadata- Calling private methods- Changing private fields- Getting private events (*)- Creating private classes

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Tools

- MSIL Disassembler (Ildasm.exe) (.NET Framework)

- Lutz Roeder's .NET Reflector

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Questions?

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TThank Youhank You