Try with this expression
dt.AsEnumerable.ToList.ForEach(Sub(row)
If DateTime.ParseExact(row("Date").Tostring,"MM/dd/yyyy hh:mm:ss",Nothing,System.Globalization.CultureInfo.InvariantCulture,System.Globalization.DateTimeStyles.None,Nothing).ToString) Then
row("Date")= DateTime.ParseExact(row("Date").Tostring,"MM/dd/yyyy",System.Globalization.CultureInfo.InvariantCulture)
End If
End Sub
)
Regards
Gokul