Offline Storage Using IndexedDB

Question

Requirement: To create a web application in ASP.NET targeting mobile devices, especially ipads which will have the "Offline Storage Functionality" when the app is not connected to internet.

My Plan:

1. To use "IndexedDB" in order to store data when not connected to internet.
2. To use ASP.NET to pull data stored offline and sync it with MSSQL Server.

I Achieved:

1. CRUD using IndexedDB.

I'm Unaware Of:

1. How to use ASP.NET to pull data stored offline and sync it with MSSQL Server when app is connected to internet.

How do I achieve my requirement? Your time and help are greatly appreciated.