Implement One Signal In MVC.

This has clear information with steps : https://youtu.be/8bqTmD5Tpjc

Steps : Call window.plugins.OneSignal.getIds and store ids.userId from the callback. You can then make a POST call to the https://onesignal.com/api/v1/notifications endpoint from your ASP.NET code setting the include_player_ids to the userId retrieved from your app. There is an ASP.NET example towards the bottom of the endpoint documentation page listed below. https://documentation.onesignal.com/reference#create-notification