Load date type data in dropdownlist

Hi.
I have one problem that I need the load data from my Sql table into dropdownlist. Data is in date format. I need to load the data in yyyy-MM-dd format without time.
Here is my code
Dim ds As New DataSet Dim SqlAdp As SqlDataAdapter = New SqlDataAdapter("Select dateofmonthly from PaidDetails where SID='" & Me.txtRegNo.Text & "' and Statuspay='N' order by Nomonths", conn) SqlAdp.Fill(ds)
Me.cbodate.DataSource = ds.Tables(0).DefaultView Me.cbodate.DataValueField = "dateofmonthly" Me.cbodate.DataBind()
conn.Close()
dateofmonthly is in date formate with time. I need date format in dropdown like 2013-10-25
Please help me
Maideen

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