Sometimes, we just want to release a single .exe file without a mass of .dll library files. This makes users easier to copy the file, and does not unveil the information of libraries used in the program.

ilmerge.exe /out:c:\\test.exe d:\project\DNSSwitcher.exe d:\project\Newtonsoft.Json.dll /target:winexe /targetplatform:v4,c:\Windows\Microsoft.NET\Framework64\v4.0.30319

Note: If you use /target:exe , there will be a command line prompt window when executing the exe file.
Reference:
http://stackoverflow.com/questions/10137937/merge-dll-into-exe
https://www.microsoft.com/en-us/download/details.aspx?id=17630