c# - How to display a date value stored in database in a dropdown in C#

Question

I have a form that has 2 dropdowns.

First dropdown and with ajax I fill the second dropdown onclick of button I store both these values in database.

Now i want to display the stored value in the dropdown bt i am nt understanding how shall i do this.

 public void ddldropdown1_SelectedIndexChanged(object sender, EventArgs e)
{
        IApplicationContext ctx = ContextRegistry.GetContext();
        IServices reg = (IServices)ctx.GetObject("Services");

        Int16 ID = Convert.ToInt16(ddldropdown1.SelectedValue);

        if (ID != 0)
        {
            IList listDate = reg.getDateList(ID);
            int Count = listDate.Count;

            for (int i = 0; i < Count; i++)
            {
                DateList obj = new DateList();
                obj = (DateList)listDate[i];
                string strDate = obj.selectDate.Day.ToString() + "/" + obj.selectDate.Month.ToString() + "/" + obj.selectDate.Year.ToString();
                ddlDatedropdown.Items.Add(new ListItem(strDate, strDate));
                }
            }
        }

//Code for Save button

   protected void btnSave_Click(object sender, EventArgs e)
{
    IApplicationContext ctx = ContextRegistry.GetContext();
    IServices reg = (IServices)ctx.GetObject("Services");

    int Dropdown1ID = Convert.ToInt32(ddldropdown1.SelectedValue);
    string strDate = "";

    strDate = ddlDatedropdown.SelectedValue.Split("/".ToCharArray())[1] + "/" +    ddlDatedropdown.SelectedValue.Split("/".ToCharArray())[0] + "/" + ddlDatedropdown.SelectedValue.Split("/".ToCharArray())[2];

    DateTime SelectDate = Convert.ToDateTime(strDate);

    if(reg.confirmGDPIRegistration(Dropdown1ID , strDate))
    {
        messagebox.show("saved");
    }
}

Inside the aspx Page i hav declared the second dropdown like this -

<asp:DropDownList ID="Datedropdown" runat="server">
                    <asp:ListItem Value = "-- Select --">-- Select --</asp:ListItem>
                </asp:DropDownList>

Inorder to display i do this-

   DataSet ds = reg.getData(PID);
   if (ds.Tables.Count> 0)
   {
       ddldropdown1.SelectedValue = ds.Tables[0].Rows[0]["ID"].ToString();
       //how to do this for date????
   }

For the First Dropdown i can fetch the value, but my question is:

• How can I fetch and display the date for the second dropdown?