Hello, Queen
The sender object is Gridview object, you could cast it to GridView type as Nagarjuna said. Do you want to get the GridViewRow object, if so, you need to write like this
GridViewRow deleteRow = this.GridView1.Rows[e.RowIndex];
If this is not what you want, please post your delete event here, we could help you according your code.
Thanks
Chao