紧急求助！vb.net 取不到oracle存储过程返回值

b/s架构vb.net程序调用oracle存储过程，同一个程序其他模块调用没问题，这一个模块调用也没问题，但取不到返回值，不知道什么原因，求高手解答，着急！
vb.net代码

Public Structure ST_trans_Search

        <DataContract()> _

            Structure ST_trans_Search_info

            <DataMember()> _

            Dim mcht_id As String

            <DataMember()> _

            Dim Settle_date As String

            <DataMember()> _

            Dim orderno As String

            <DataMember()> _

            Dim cardno As String

            <DataMember()> _

            Dim amt As Double

            <DataMember()> _

            Dim TranDate As String

            <DataMember()> _

            Dim TranTime As String

            <DataMember()> _

            Dim trace As String

            <DataMember()> _

            Dim page_count As String



        End Structure

        Dim page_count As Integer

        Dim trans_info As List(Of ST_trans_Search_info)

    End Structure



    <OperationContract()> _

    Public Function Trans_Search(ByVal Merch_id As String, ByVal Settle_date As String, ByVal orderno As String, ByVal cardno As String, ByVal amt As Double, ByVal TranDate As String, ByVal TranTime As String, ByVal trace As String, ByVal PageSize As Integer, ByVal CurrPage As Integer) As ST_trans_Search

        On Error GoTo go_Err



        Dim s_trans As ST_trans_Search

        Dim s_trans_info() As ST_trans_Search.ST_trans_Search_info = Nothing

        '=================带参数存储过程 

        Dim myconnection As OracleConnection

        Dim strsql = "User ID=card;Password=card;Data Source=orcltest"     'OK测试大机Oracle   test_Esa_Web_Opr_Orcl

        myconnection = New OracleConnection(strsql)

        myconnection.Open()



        Dim oraclecomm As OracleCommand = Nothing

        oraclecomm = New OracleCommand("trans_search", myconnection)

        oraclecomm.CommandType = CommandType.StoredProcedure

        oraclecomm.Parameters.Add("Merch_id", OracleType.VarChar, 50)

        oraclecomm.Parameters("Merch_id").Direction = ParameterDirection.Input

        oraclecomm.Parameters("Merch_id").Value = Merch_id



        oraclecomm.Parameters.Add("Settle_date", OracleType.VarChar, 50)

        oraclecomm.Parameters("Settle_date").Direction = ParameterDirection.Input

        oraclecomm.Parameters("Settle_date").Value = Settle_date



        oraclecomm.Parameters.Add("orderno", OracleType.VarChar, 50)

        oraclecomm.Parameters("orderno").Direction = ParameterDirection.Input

        oraclecomm.Parameters("orderno").Value = orderno



        oraclecomm.Parameters.Add("cardno", OracleType.VarChar, 50)

        oraclecomm.Parameters("cardno").Direction = ParameterDirection.Input

        oraclecomm.Parameters("cardno").Value = cardno



        oraclecomm.Parameters.Add("amt", OracleType.Number)

        oraclecomm.Parameters("amt").Direction = ParameterDirection.Input

        oraclecomm.Parameters("amt").Value = amt



        oraclecomm.Parameters.Add("TranDate", OracleType.VarChar, 50)

        oraclecomm.Parameters("TranDate").Direction = ParameterDirection.Input

        oraclecomm.Parameters("TranDate").Value = TranDate



        oraclecomm.Parameters.Add("TranTime", OracleType.VarChar, 50)

        oraclecomm.Parameters("TranTime").Direction = ParameterDirection.Input

        oraclecomm.Parameters("TranTime").Value = TranTime



        oraclecomm.Parameters.Add("trace", OracleType.VarChar, 50)

        oraclecomm.Parameters("trace").Direction = ParameterDirection.Input

        oraclecomm.Parameters("trace").Value = trace



        'oraclecomm.Parameters.Add("respcode", OracleType.VarChar, 50)

        'oraclecomm.Parameters("respcode").Direction = ParameterDirection.Input

        'oraclecomm.Parameters("respcode").Value = respcode



        oraclecomm.Parameters.Add("pagesize", OracleType.Number)

        oraclecomm.Parameters("pagesize").Direction = ParameterDirection.Input

        oraclecomm.Parameters("pagesize").Value = PageSize



        oraclecomm.Parameters.Add("currpage", OracleType.Number)

        oraclecomm.Parameters("currpage").Direction = ParameterDirection.Input

        oraclecomm.Parameters("currpage").Value = CurrPage



        oraclecomm.Parameters.Add("recordcount", OracleType.Number)

        oraclecomm.Parameters("recordcount").Direction = ParameterDirection.InputOutput



        oraclecomm.Parameters.Add("pp_cursor", OracleType.Cursor)

        oraclecomm.Parameters("pp_cursor").Direction = ParameterDirection.Output



        'Dim aa12 As System.IO.StreamWriter = New System.IO.StreamWriter("D:\程序\ESA_OPR_NEW\ESA_WEB_MER\File_MerReport\aaa\" & Merch_id.ToString & "__" & Year(Now()) & Month(Now()) & Day(Now()) & Hour(Now()) & Minute(Now()) & Second(Now()) & "__" & "__ .txt", False, System.Text.Encoding.Unicode)

        'aa12.WriteLine(oraclecomm.Parameters("recordcount").Value.ToString() + "aaa")   '    ds.Rows(0).Item("name")    MyReader("name")   输出参数oraclecomm.Parameters("recordcount").Value.ToString()

        'aa12.Close()

        'aa12.Dispose()



        Dim da1 As New OracleDataAdapter()

        da1.SelectCommand = oraclecomm

        Dim ds As New DataTable()

        da1.Fill(ds)

        myconnection.Close()



        For j = 0 To ds.Rows.Count - 1

            If s_trans_info Is Nothing Then

                ReDim s_trans_info(0)

            Else

                ReDim Preserve s_trans_info(UBound(s_trans_info) + 1)

            End If

            s_trans_info(UBound(s_trans_info)).mcht_id = Trim(ds.Rows(j).Item("merch_id"))

            s_trans_info(UBound(s_trans_info)).Settle_date = Trim(ds.Rows(j).Item("Settle_date"))



            If Trim(ds.Rows(j).Item("orderno")) = "0" Then

                s_trans_info(UBound(s_trans_info)).orderno = ""

            Else

                s_trans_info(UBound(s_trans_info)).orderno = Trim(ds.Rows(j).Item("orderno"))

            End If



            If Trim(ds.Rows(j).Item("cardno")) = "0" Then

                s_trans_info(UBound(s_trans_info)).cardno = ""

            Else

                s_trans_info(UBound(s_trans_info)).cardno = Trim(ds.Rows(j).Item("cardno"))

            End If



            s_trans_info(UBound(s_trans_info)).TranDate = FormatDateTime(ds.Rows(j).Item("trandate"), DateFormat.ShortDate)



            If Trim(ds.Rows(j).Item("amt")) = "0" Then

                s_trans_info(UBound(s_trans_info)).amt = ""

            Else

                s_trans_info(UBound(s_trans_info)).amt = Trim(ds.Rows(j).Item("amt"))

            End If



            If Trim(ds.Rows(j).Item("TranDate")) = "0" Then

                s_trans_info(UBound(s_trans_info)).TranDate = ""

            Else

                s_trans_info(UBound(s_trans_info)).TranDate = Trim(ds.Rows(j).Item("TranDate"))

            End If



            If Trim(ds.Rows(j).Item("TranTime")) = "0" Then

                s_trans_info(UBound(s_trans_info)).TranTime = ""

            Else

                s_trans_info(UBound(s_trans_info)).TranTime = Trim(ds.Rows(j).Item("TranTime"))

            End If



        Next

        s_trans_info(0).page_count = oraclecomm.Parameters("recordcount").Value.ToString()   '记录总数



go_exit:

        s_trans.trans_info = s_trans_info.ToList

        Return s_trans

        Exit Function

go_Err:

        s_trans_info = Nothing

        GoTo go_exit

    End Function