Datasheet

Chapter 1: Introducing C#

C#application

code

AssemblyCompilation

Figure 1-2

2. That code is compiled into MSIL, which is stored in an assembly (see Figure 1 - 2 ).

3. When this code is executed (either in its own right if it is an executable or when it is used from

other code), it must first be compiled into native code using a JIT compiler (see Figure 1 - 3 ).

Assembly

Native Code

JIT Compilation

Figure 1-3

4. The native code is executed in the context of the managed CLR, along with any other running

applications or processes, as shown in Figure 1 - 4 .

Native Code

.NET CLR

System Runtime

Native Code Native Code

Figure 1-4

Linking

Note one additional point concerning this process. The C# code that compiles into MSIL in step 2 needn ’ t

be contained in a single file. It ’ s possible to split application code across multiple source code files, which

are then compiled together into a single assembly. This extremely useful process is known as linking . This

is because it is far easier to work with several smaller files than one enormous one. You can separate out

logically related code into an individual file so that it can be worked on independently and then

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