Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index error @ line 4 I have marked it..
M using webusercontrol to insert Value
protected void RadGrid1_UpdateCommand(object sender, GridCommandEventArgs e) { GridEditableItem editeditem = (GridEditableItem)e.Item; UserControl userControl = (UserControl)e.Item.FindControl(GridEditFormItem.EditFormUserControlID); string ID1 = editeditem.OwnerTableView.DataKeyValues[editeditem.ItemIndex]["ID"].ToString(); //HiddenField hddn = (HiddenField)userControl.FindControl("HiddenField1"); TextBox city1 = (TextBox)userControl.FindControl("TextBox1"); DropDownList ddpl1 = (DropDownList)userControl.FindControl("DropDownList1"); string updatequery = String.Format("UPDATE MST_City set City='{0}', StateID='{1}' where ID='{2}'", city1.Text, ddpl1.SelectedValue, ID1); con.Open(); using (SqlCommand sql = new SqlCommand() { CommandText = updatequery, Connection = con }) { sql.ExecuteNonQuery(); } con.Close(); }