datetime issues in asp.net c# with ajax control tool kit

hi all

created a web form with a textbox for date field like below

<asp:TextBox ID="DateTextBox" runat="server" AutoPostBack="false"></asp:TextBox>
<ajaxToolkit:CalendarExtender ID="CalendarExtender1" runat="server" TargetControlID="DateTextBox" Format="dd-MM-yyyy" />

then insert to database
but stored value in database is like 2015-06-08 00:00:00.000 don't have time.

I want to store like 2015-06-15 11:47:54 AM

means date and time

how do this?

I am using asp.net c# web form