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How can I produce an assembly?

An assembly can produce from a .Net compiler.
For Example, the following C# program:
public class CDemo 
{ 
public CDemo() 
{ 
System.Console.WriteLine( "Hello from CDemo" );
} 
}
Can be compiled into a dll as: 
Csc/t:library cdemo.cs

Now the contents of assembly can be view through opening the ''IL Disassembler'' tool of .Net SDK.

Also compiling source into modules and then using assembly linker (al.exe) for combining them to generate assembly.