Check Box List values to be stored in binary values in ASP.NET

Hi All,
I have Check Box list in Asp.Net, contains week days like as (Monday to Sunday)
I want to store the checked values as 1, non checked values as 0,  as Binary format.
Say for example: 0000011 (Monday ,Tuesday selected)
<
asp:CheckBoxList ID="chlSupportDays" runat="serve ...