อยากทราบการใช้งาน calendar เพื่อที่จะ select Data จาก ดาต้าเบสมาโชว

<asp:Calendar ID="MyCalendar" 
                      runat="server" AutoPostBack="true"
                      BackColor="White" 
                      BorderColor="Black" 
                      Font-Names="Times New Roman" 
                      Font-Size="10pt" 
                      ForeColor="Black" 
                      Height="220px" 
                      NextPrevFormat="FullMonth" 
                     
                      OnSelectionChanged="MyCalendar_SelectionChanged" 
                      SelectionMode="DayWeek" 
                      Width="400px" DayNameFormat="Shortest" TitleFormat="Month" 
                        SelectedDate="12/23/2014 08:26:51">
            <SelectedDayStyle BackColor="#CC3333" ForeColor="White" />
            <OtherMonthDayStyle ForeColor="#999999" />
            <TodayDayStyle BackColor="#CCCC99" />
                         <DayStyle Width="14%" />
            <NextPrevStyle 
                           Font-Size="8pt" 
                           ForeColor="White" />
            <DayHeaderStyle Font-Bold="True" Font-Size="7pt" BackColor="#CCCCCC" ForeColor="#333333" 
                             Height="10pt" />
                         <SelectorStyle BackColor="#CCCCCC" Font-Bold="True" Font-Names="Verdana" 
                             Font-Size="8pt" ForeColor="#333333" Width="1%" />
            <TitleStyle BackColor="Black" 
                        Font-Bold="True"
                        Font-Size="13pt" 
                        ForeColor="White" Height="14pt" />
        </asp:Calendar>

protected void button2_Click(object sender, EventArgs e)
        {
            String strSQL;
            strSQL = "SELECT * FROM ADMS_Machining where datetime = '" + this.Label4.Text + "'"; 

            SqlDataReader dtReader;
            objCmd = new SqlCommand(strSQL, objConn);
            dtReader = objCmd.ExecuteReader();

            //*** BindData to Repeater ***//*
            myRepeater.DataSource = dtReader;
            myRepeater.DataBind();

            dtReader.Close();
            dtReader = null; 
        }

        protected void MyCalendar_SelectionChanged(object sender, EventArgs e)
        {
            Label4.Text = "You selected these dates:<br />";

            foreach (DateTime dt in MyCalendar.SelectedDates)
            {
                Label4.Text += dt.ToLongDateString() + "<br />";
            }

        }