There are several Visual Studio extensions for Antlr: Antlr4Code, ANTLR Language Support, Actipro SyntaxEditor for WPF, and Syntax Highlighting Pack. However, each has problems (works on Antlr3, has advertisements, does not offer a “go to definition” right-click context menu command, etc). So, over the last few days, I implemented a simple VS 2015/2017 extension for Antlr4 grammars. You can find the sources on Github (https://github.com/kaby76/AntlrVSIX). The extension implements “go to definition” and “find all references” for grammar symbols. There are some restrictions, but it’s a start, works well, and is very simple code. Enjoy!
(Edited Jan 14, 2017)