GET VALUE FROM DROPDOWNLIST

string ContentName = e.Values["ContentName"].ToString();         
         
// Get Value from DropDown
int TopicID = 0;
foreach (DetailsViewRow row in ItemsDetailsView.Rows)
{
    if (row.Cells[0].Text == "Topic")
    {
         DropDownList TopicDropDown = (DropDownList)row.Cells[1].FindControl("Topic_TopicIDList");
         TopicID = int.Parse(TopicDropDown.SelectedValue.ToString());
    }

}