请看以下代码，明明R1和currenttable.current是同一行，为什么R1取得的关联子表的行数为0呢？

Dim InputSRS As String = "BR1610-03347"

If Inputsrs <> "" Then

    Dim r1 As DataRow = DataTables("MainSchedule").SQLFind("SrsNO = \'" & Inputsrs & "\'") \'   

If r1 IsNot Nothing Then

        Output.Show("identify =" & r1("_identify"))

        If r1.GetChildRows("ProcessSchdule") IsNot Nothing Then

           Output.Show(r1.GetChildRows("ProcessSchdule").Count)            

        End If

End If

End If

Output.Show("identify =" & CurrentTable.Current("_identify"))

Output.Show(CurrentTable.Current.DataRow.GetChildRows("ProcessSchdule").Count)