the following code retrieve all activities start and end in the same date that picked by user , what i need retrieve all activities that the date picked by user in the period of the activate 

for example
 activity start on 25 march and end on 25 march too that the code will retrieve but what i need is to retrieve activities started before 25 and end after 25 or start before 25 and end in 25 and activities start on 25 and after 25 

OR YOU CAN SEE MY PIC MY CODE IS DOING A BUT I WANT TO DO A , B ,C AND D
<http://im46.gulfup.com/4Cudk8.jpg>

```
 Public Shared Function SelectByDate(ActivityDate As Date) As List(Of vActivity)

        Dim st As Date = ActivityDate
        Dim et As Date = st.AddDays(1).AddSeconds(-1)

       Using ctx As New ActivitiesEntities
            Dim Lst = (From actv In ctx.vActivities
                       Select actv
                       Where actv.StartTime >= st And actv.EndTime <= et
                       Order By actv.StartTime)

            Return Lst.ToList
        End Using
    End Function

```