Note: The changes in the data will be persisted per Session only. The data will be reset next time you visit the page.

In addition to the server/ajax delete feature of Telerik RadGrid there is already client-side delete available which allows you to erase records without making a round trip to the server. This optimizes the performance and the source data is automatically refreshed on the subsequent post to the server. The user experience is improved because the delete action is done client-side and the table presentation is updated immediately.

In order to trigger client-side delete action you need to add GridClientDeleteColumn to the set of columns. This column is special type of GridButtonColumn designated for the task. It has ConfirmText property which can be assigned like with the default GridButtonColumn.

The client-side delete feature supports:

• NoRecordsTemplate (including hierarchy)
• Hierarchy (no matter client/server or ajax)
• The editing data functionality will remain unaffected
• Automatic deletes with data source control under ASP.NET 2.0
• Manual delete with ability to cancel the delete action in the corresponding DeleteCommand/ItemCommand handler (by setting e.Canceled to true)

You can review this topic from the product documentation for additional info:
Client-side delete