How to install Visual Studio Code extensions from Command line

To add to Shan Khan's answer above, if you want to install extensions in a .bat file, you have to use the call keyword, otherwise your script exits after the extension installation completes. Also, if code.exe is not already in the path and you are calling using a full path, make sure you're pointing at the /bin directory:

echo.
echo.
echo Installing VS Code Extensions...
call "C:\Program Files\Microsoft VS Code\bin\code" --install-extension ritwickdey.liveserver
call "C:\Program Files\Microsoft VS Code\bin\code" --install-extension ritwickdey.live-sass
call "C:\Program Files\Microsoft VS Code\bin\code" --install-extension ms-vscode.csharp
call "C:\Program Files\Microsoft VS Code\bin\code" --install-extension PKief.material-icon-theme
echo Done.
echo.
echo.

To make it easier to automate and configure VS Code, it is possible to list, install, and uninstall extensions from the command line. When identifying an extension, provide the full name of the form publisher.extension, for example donjayamanne.python.

code --list-extensions
code --install-extension ms-vscode.cpptools
code --uninstall-extension ms-vscode.csharp

Documentation

According to the documentation, you can use --install-extension for that. For example:

code --install-extension ms-vscode.csharp