how to pass particular column rows rows vise values to a procedure like EventId

for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
            {
                 ds = obj.GetPartEventReportnew(Convert.ToInt32(dlstEventUsercount.Tables[0].Rows[i]["Event_Id"]), attendeeId, fromdate, todate);
            }

how to remove dropdownlist all rcods through java script

 document.getElementById("ctl00$ContentPlaceHolder1$G_drpGD_Type").length = 0;

Date Filtering on Store Procedure

Create procedure [dbo].[PMP_GetPartEventReportnew]  
@Event_Id int, 
@Attendee_Id int,
@Fromdate datetime,
@Todate datetime
AS               
Begin 
select distinct e.Event_Id,ex.Amount,s.State_initials,sim.SpendItem_Name 
from PMP_EventInformation e 
JOIN PMP_StateMaster s ON e.Event_State_Id = s.State_Id 
JOIN PMP_Expenses ex ON e.Event_Id = ex.Eventid 
JOIN PMP_AttendeeInformation ea ON ex.Attendeeid = ea.Attendee_Id 
JOIN PMP_SpendItemMaster sim ON ex.SpendItemid = sim.SpendItem_id  
where e.Event_Id = @Event_Id and ex.Attendeeid = @Attendee_Id  
and CONVERT(VARCHAR(50),ex.Date_Submitted,121) between CONVERT(VARCHAR(50),@Fromdate,121) and CONVERT(VARCHAR(50),@Todate,121)
Order By e.Event_Id 
end