If you have Visual Studio up and running while you edit the project files in a separate window under Vim, every time you switch back to Visual Studio, it looks at the on-disk timestamps for every file you have open in Visual Studio, including the project file. For each file that changed since you switched away from Visual Studio, it asks if you want to reload it from disk.
It even asks if you want to just reload everything that's changed, so you can edit multiple files without Alt-Tabbing back to Visual Studio after each edit.
Building from Vim
If you're using Visual Studio 2010 or newer, they've switched to MSBuild for Visual C++ projects. (Prior to that, MSBuild was only for projects in .NET languages.) That means you can integrate MSBuild into Vim as a build system:
:set errorformat=\ %#%f(%l\\\,%c):\ %m
:set makeprg=msbuild\ /nologo\ /v:q\ /property:GenerateFullPaths=true
(Swiped from here.)
Visual-Studio-Like Command Key Mappings
These command mappings are inspired by old versions of Visual Studio:
map <S-F4> :cp<cr>
map <F4> :cn<cr>
map <F5> :make run<cr>
map <F7> :make<cr>
Microsoft keeps changing these command keys, and I keep switching them back when installing new versions, so I can't remember what they're using these days. Adjust to taste.
Emulating Vim Inside Visual Studio
Now, there's another way to go entirely here: emulate Vim inside Visual Studio!
This was once the province of only those who bought Visual Studio Professional or higher, but with the release of Visual Studio 2015, the free version finally has the ability to load third-party extensions. There are a couple of them that do this:
VsVim, a free extension available through the Visual Studio Gallery
ViEmu, a commercial extension. Presumably it's better in some way, else they wouldn't still be in business.
Or, you can go join the cool kids and start using Visual Studio Code, which has at least three Vim emulator extensions. I haven't test-driven them extensively, but here they are ordered by how well they matched my expectations of how a Vim emulation should behave:
To install any of them, just hit Ctrl-Shift-P (Windows) inside Visual Studio code, type
Extensions: Install Extension, then type
vim. All three will come up, along with a few other things which are not Vim emulators for VSCode.
None of those extensions are flawless.
(I say this as one who uses Vim daily, and installs such extensions only to ease the transition when I do occasionally have to use Visual Studio and VSCode.)