.NET is a software framework and platform developed by Microsoft that runs primarily on Microsoft Windows. It includes a large class library called Framework Class Library (FCL) and provides language interoperability across several programming languages. Some key aspects include the Common Language Runtime (CLR) which handles memory management, exception handling and security, and supports languages like C#, Visual Basic .NET and F#. The .NET Framework also includes APIs for building Windows-based applications, web applications and web services.

1. Introduction to .NET
Lorenzo Dematté
@ldematte

2. What is .NET?
Not different from asking: what is Java?
.NET, XP, 2000… oh my!
A Framework
Execution environment (CLR)
Support libraries (BCL)
Languages (C#, VB, F#)

3. .NET is also
A platform, an “ecosystem”
Both MS and others
Tools (VS), libraries, open source projects (Nunit,
EF)
And also, for some parts, a specification
/standard
CLI, C#

4. .NET Framework
C# C++/CLI VB.NET F#
PLINQ TPL
EF LINQ
ADO.NET WPF WCF WF
BCL VS
CLR (Jitter, VM, Loader, GC, Debugging…)
Host: OS, Hardware, Exe (SQL, IIS)

5. History
1.0, 1.1
Winforms, C# 1, ASP.NET, ADO.NET
2.0
Generics, C# 2 (latest CLR)
3.0 – “WinFX”
WPF, WCF, WF
3.5
LINQ, C# 3 (lambda, extension methods)
4.0
ParallelFX, C# 4 (dynamic)
4.5
Metro, C# 5 (async)

6. .NET Framework (history)
PLINQ TPL F#
EF LINQ
ADO.NE
T WPF WCF WF
C++/CLI
BCL
VB.NET
CLR (Jitter, VM, Loader, GC,
Debugging…) C#

8. Core concepts
Managed
Garbage collection
Introspection (self-description)
Virtual machine
JIT
Verification and optimization
Components
Assembly
Bytecode + Metadata

9. Where?
Windows
Linux, MacOSX
Mono, MonoMAC
Embedded
Windows CE, Windows Phone
Micro
Netduino

10. Outside MS: Languages

11. Outside MS: Libraries

12. From source to execution:
languages
Compilation
csc /out:test.exe test.cs
mcs test.cs --out:test2.exe
Execution
.test.exe
mono test.exe
Multiple languages
csc /t:library /out:testLib.dll testLib.cs
fsc test.fs /r:testLibrary.dll

13. From source to execution
Assembly:
MSIL + Metadata
Load assembly
Plus dependencies
“Fusion”
JIT

14. From source to execution
Assembly (dll)
F# source
MSIL
Assembly
(exe)
C# source
MSIL
Main Func
ASM Main
Greet Func
GreetAll Func
CLR (Jitter, VM, Loader, GC, Debugging…)

15. An example: Hello World