Is there any built-in, add-in solution for visual studio to compare two files and display result with differences? I could't find one...
Visual Studio 2005 Team Edition has a built in version (based on WinDiff?) but you can incorporate third party tools e.g.
Beyond Compare which I regularly use.
See here for how-to.
Not that I know of, but Beyond Compare is probably worth a look anyway.
That functionality appears to be related to Source Control. So it is really as source control issue.
If you are not using Source Control - You should be - Try The Vault from www.sourcegear.com for a good (and free for one user) commercial source control system. There are others and they should come with a comparision tool (The Vault has one and its installed into VS when you install the vault client and connect to a source controlled project).
Depending on your use case I'd recommend VisualSVN. You'll get the source control feature of SVN built into the VS IDE plus the ability to compare any source code file with any checked in version file from SVN.
It installs all the prerequites for you SVN (Subversion), TortoiseSVN, Diff, AND VisualSVN (The Visual Studio Integration).
It also has a nice quick windows installer for the SVN server which worries about apache etc. so you don't have to.
Essential for the non linux geek, it it not free but at $49 it is a bargain,
SlickEdit Tools Versioning Toolbox has the same diff tool built in as the SlickEdit programmer's editor. The Versioning Toolbox is not free but isn't that expensive either. The diff tool is very nice.
I use WinMerge. Not as good as Beyond Compare but it's free and open source.
Also check out Visual Studio Comparison Tools, it's a Visual Studio add-in that connects it to WinMerge.
Here is an excellent post that describes integration of many 3rd party diff and merge tools into Visual Studio - including araxis, beyond compare, WinMerge and many others. The post is badly needed, since the command-line parameters that VS can supply aren't fully documented.
Personally, I switched from the built-in tool to Araxis, and am generally happy with it. I am also curious about bazaar, which supposedly (according to the colorful author of its diff-component), "solves the diff problem"... Anyone has any experience with that?
Hello. As for me, CodeCompare is a useful solution for your task. You can compare, merge and edit data within one environment - in the Visual Studio.
You can try CompareEnter. With it, you can compare the active file in Visual Studio or the containing folder by using external comparison software.