#11 – Examine IL Using Ildasm.exe

In .NET, source is compiled to an platform-neutral intermediate language called Common Intermediate Language.  The IL is later compiled into native code at runtime, running in a virtual machine.

You can examine the IL for your applications by running a tool called the IL Disassembler (ildasm.exe).  You can find ILDasm in a directory that looks something like this:

C:\Program Files (x86)\Microsoft SDKs\Windows\v7.0A\Bin\x64

Alternatively, you can just type “ildasm” in the Start Menu search box in Windows 7 or Windows Vista.

ILDasm will show you three basic things:

  • A list of all classes and methods in your assembly
  • The contents of the assembly’s manifest
  • IL code for any method implemented in the assembly.

Here’s an example of what is displayed in ILDasm.