Difference between Build Solution, Rebuild Solutio

Question

What is the difference between Build Solution, Rebuild Solution, and Clean Solution in Visual Studio?

When is the appropriate time to use each one of these?

Answer 1

• Build solution will perform an incremental build: if it doesn't think it needs to rebuild a project, it won't. It may also use partially-built bits of the project if they haven't changed (I don't know how far it takes this)
• Rebuild solution will clean and then build the solution from scratch, ignoring anything it's done before. The difference between this and "Clean, followed by Build" is that Rebuild will clean-then-build each project, one at a time, rather than cleaning all and then building all.
• Clean solution will remove the build artifacts from the previous build. If there are any other files in the build target directories (bin and obj) they may not be removed, but actual build artifacts are. I've seen behaviour for this vary - sometimes deleting fairly thoroughly and sometimes not - but I'll give VS the benefit of the doubt for the moment :)

(The links are to the devenv.exe command line switches, but they do the same as the menu items.)

Answer 2

The one major thing I think people are leaving out is that Build and Clean are both tasks that are performed based on Visual Studio's knowledge of your Project/Solution. I see a lot of complaining that Clean doesn't work or leaves leftover files or is not trustworthy, when in fact, the reasons you say it isn't trustworthy actually makes it more trustworthy.

Clean will only remove (clean) files and/or directories that Visual Studio or the compiler themselves have in fact created. If you copy your own files or files/folder structures get created from an outside tool or source, then Visual Studio doesn't "know they exist" and therefore, should not touch them.

Can you imagine if the Clean operation basically performed a "del *.*" ? This could be catastrophic.

Build performs a compile on changed or necessary projects.

Rebuild performs a compile regardless of change or what's necessary.

Clean removes files/folders it has created in the past, but leaves anything that it didn't have anything to do with, initially.

I hope this elaborates a bit and helps.

Answer 3

All I know is a Clean does not do what "make clean" used to do - if I Clean a solution I would expect it delete obj and bin files/folders such that it builds like is was a fresh checkout of the source. In my experience though I often find times where a Clean and Build or Rebuild still produces strange errors on source that is known to compile and what is required is a manual deletion of the bin/obj folders, then it will build.

Answer 4

Build solution: Compiles code files (DLL and EXE) which are changed.

Rebuild: Deletes all compiled files and compiles them again irrespective if the code has changed or not.

Clean solution: Deletes all compiled files (DLL and EXE file).

You can see this YouTube video (Visual Studio Build vs. Rebuild vs. Clean (C# interview questions with answers)) where I have demonstrated the differences and below are visual representations which will help you to analyze the same in more detail.

The difference between Rebuild vs. (Clean + Build), because there seems to be some confusion around this as well:

The difference is the way the build and clean sequence happens for every project. Let’s say your solution has two projects, “proj1” and “proj2”. If you do a rebuild it will take “proj1”, clean (delete) the compiled files for “proj1” and build it. After that it will take the second project “proj2”, clean compiled files for “proj2” and compile “proj2”.

But if you do a “clean” and build”, it will first delete all compiled files for “proj1” and “proj2” and then it will build “proj1” first followed by “proj2”.

Answer 5

Taken from this link:

Build means compile and link only the source files that have changed since the last build, while Rebuild means compile and link all source files regardless of whether they changed or not. Build is the normal thing to do and is faster. Sometimes the versions of project target components can get out of sync and rebuild is necessary to make the build successful. In practice, you never need to Clean.

Answer 6

Build Solution – Builds any assemblies which have changed files. If an assembly has no changes, it won’t be re-built. Also will not delete any intermediate files.

Rebuild solution will clean and then build the solution from scratch, ignoring anything it’s done before

Clean Solution will delete all compiled files (i.e., EXE’s and DLL’s) from the bin/obj directory.