ASP.NET, what is a datagrid bound to after postback?

I have a gridview full of telephone numbers. To populate the gridview I bind the gridview's datasource to a List<> of telephone numbers. I do this when the page is first loaded, but not on postbacks.

I want the user to be able to delete some of the telephone numbers, and then, if they want, click a Save button, and this will update the database, otherwise their changes will be ignored. So I have a button in the grid, and an event is fired, and I can call DeleteRow(row index) and remove the row from inside this event. For some reason this doesn't work.

All the gridview examples I find on the Internet execute the delete straight away by calling an sql function, and then bind again. And some examples bind the grid every time the page ios loaded, which seems inefficient.

My questions is: The delete button causes 开发者_如何学Goa postback to the server. On postback the list of telephone numbers no longer exists. And the gridview's datasource is null. The grid is no longer bound. But there must be data somewhere, because the data in the grid is still visiable. Where is this data, and can I delete a row of it, so that a row in the gridview is deleted?

The viewstate saves the contents of the datagrid, so the answer is "The Viewstate"

Understanding the viewstate is essential to understanding how ASP.NET works, so rather than posting just enough info to answer your question, I'm going to recommend you read the entire article I linked to.

You can use jquery , you need to save the Datakey value of each deleted row in a hidden field and hide the selected row , and when user clicks save , u can delete the rows based on hidden field values @ code behind.