Can a .NET windows application be compressed into a single .exe?
I am not too familiar with .NET desktop applications (using Visual Studio 2005). Is it possible to have the entire application run from a single .exe file?
Solution 1:
Yes, you can use the ILMerge tool. It is also available as a NuGet package.
Solution 2:
Today, in 2015, you can use Costura.Fody for this. Using it amounts to adding the NuGet package to your project and recompiling. I'm not sure if it works with Visual Studio 2005 as in the question, but then it's not year 2008 either. I've used it in a few of my projects and it worked great.
Fody is a general purpose Code Weaver that is free and open source. The basic idea that it allows post-processing of the compiled .NET code to enhance it with features. For example, logging can be added to every method call, etc. In our case, it's packaging the dependent DLL files into the assembly resources, so that they could be loaded during the program runtime as if they were stand-alone dependencies.
Solution 3:
Yes. In .NET you can have your entire application encapsulated as a single EXE file. Just make sure your solution only has one Windows Application project in it (and no other projects except for setups).
The EXE file created by your .NET project will not be a stand-alone executable file, but the only dependency it will have will be the .NET runtime (unless you add references to other DLL assemblies). If you use .NET 2.0 (which I recommend), the runtime comes preinstalled on newer PCs and is very easy and quick to set up on older machines (installer is about 23 MB).
If your app does need to reference other assemblies (like a data access DLL or a .NET class library DLL project), you could use one of the tools referenced by other posters here to combine your EXE and all referenced DLLs into a single EXE file. However, conventional practice would dictate simply deploying the EXE file along with any dependent DLLs as separate files. In .NET, deployment of dependent DLLs is pretty simple: just put them in the same folder as the EXE file on the client machine, and you're done.
It is good practice to deploy your application (whether one file or many) as a single-file installer (either a setup.EXE or setup.MSI). .NET comes with deployment project templates that can create installers for you fairly easily.
Slightly off-topic: You could use NGEN to compile your .NET application as a native EXE, but it would still be dependent upon the .NET runtime. The advantage of native compilation is that some things can be pre-compiled, but I've never seen a situation where this tiny performance increase is worth the bother.