Large amounts of data in C#?

Question

Hi all,
We are a VFP users for long time, using VFP with MS SQL with many different type of application. we are currently building a new application with c# and MS SQL with a large amounts of data. When we calling a query in VFP we use a CursorAdapter and you can have there is a FetchAsNeeded() function that can enable you to get a certain amount of data in a batch base and automatically can get more data when you need that.

So any body can help me to find this function in C#.

Thank you.