/Diff
Visual Studio 2012
Compares two files. The differences are displayed in a special Visual Studio window.
devenv /Diff SourceFile, TargetFile, [SourceDisplayName], [TargetDisplayName]
Compares two files. The differences are displayed in a special Visual Studio window.
devenv /Diff SourceFile, TargetFile, [SourceDisplayName], [TargetDisplayName]