How to apply i18n to support multiple languages in ASP.NET MVC?

For ASP.NET MVC part: Functions to switch language and get resource by culture:
http://www.codeproject.com/Articles/262917/i-n-globalization-with-gettext-and-asp-net-mvc
javascript -> cookie -> Base Controller/Razor view base page -> i18n lib functions

http://gnuwin32.sourceforge.net/packages/gettext.htm

How to edit PO files
#1 Online editor: edit, add, and delete etc.
https://localise.biz/free/poeditor
#2 Local open source app
http://sourceforge.net/projects/betterpoeditor/