Understanding .NET assemblies

When I build a project in a solution in Visual Studio (it can be C# VB.NET F# or else) I suppose that only one assembly per project is generated right?

So if I have a solution containing proj开发者_运维技巧ect 1 2 3 and 4 When I build one by one each project I get 4 assemblies right?

However, is there the possibility to let the builder/compiler generate only one assembly for the entire solution? Or for two projects compiled together?

I mean something like calling the compiler using the command line and setting a target assembly...

By default there is a 1 to 1 correspondence between projects and assemblies. But you can use a tool like ILMerge to create one assembly from several.