Dim kaishi As WinForm.DateTimePicker = e.Form.Controls("DateTimePicker1")
Dim jieshu As WinForm.DateTimePicker = e.Form.Controls("DateTimePicker2")
Dim filter As String = "1=1"
If kaishi.text > "" Then
    filter &= " and 接收时段 >= #" & kaishi.Text & "#"
End If
If jieshu.text > "" Then
    filter &= " and 接收时段 <=#" & jieshu.Text & "#"
End If
Tables("表A").Filter = filter

DataTables("表B").DataRows.Clear
For Each dr1 As Row In Tables("表A").rows
    Dim dr2 As DataRow = DataTables("表B").AddNew()
    For Each dc As DataCol In DataTables("表A").DataCols
        dr2(dc.Name) = dr1(dc.name)
    Next
Next

表B的DataColChanged事件

Select Case e.DataCol.Name
    Case "接收时段","操作时段"
        Dim dr As DataRow = e.DataRow
        If dr.IsNull("接收时段") OrElse dr.IsNull("操作时段") Then
            dr("耗时") = Nothing
        Else
            Dim tp As TimeSpan = dr("完成日期") - dr("开始日期")
            dr("耗时") = tp.TotalHours
        End If
End Select