Many of the C++ plug-in examples from the Maya devkit folder have been ported to C#. You can find example files in the <...>\devkit\dotnet folder of your install directory. The examples.sln and wpfexamples.sln solution files are provided. Each solution consists of one project.
One example not ported originally from C++ is the DAGExplorer example under the <...>\devkit\dotnet\wpfexamples folder. This example demonstrates several features of the .NET API including:
This step is not mandatory, but it is advisable to retain a copy of the original project files.
Each example solution consists of one project each, and generates an assembly with extension .nll.dll. After compiling, Visual Studio creates a $(SolutionDir)assemblies folder, and copies the target to this folder.