在 ADODB 记录集循环期间，vb6 中的类型不匹配错误 13

Question

Private Sub cmdShow_Click()
    'lblTotPur/lblTotPayRet/lblBalance
    Dim strShow, mSlNo
    Dim rsShow As New ADODB.Recordset
    Dim NewItem As Variant
    If Trim(txtCustomer.Text) = "" Then
        MsgBox "Please select vendor to proceed...", vbCritical, POPUP_COMP
        Exit Sub
    End If

    Dim recCnt
    pgrPartyLedger.Min = 0
    recCnt = 0
    'VOUCHMST_P//VNO,DATED,VTYPE,REMARKS,byUser CASH PURCHASE RETURN
    strShow = "select Count(*) as mCnt from VOUCHMST A,VOUCHDAT B, mPurchase C "
    strShow = strShow & " where A.VNO=B.VNO and (A.REMARKS='CASH PURCHASE RETURN' OR A.REMARKS='CREDIT PURCHASE RETURN' OR A.REMARKS='CREDIT PURCHASE' OR A.REMARKS='CASH PURCHASE' OR A.REMARKS='PAYMENT' OR A.REMARKS='CREDIT NOTE') "
    strShow = strShow & " and A.DATED between #" & Format(dtFrom.Value, "MM/dd/yyyy") & "# "
    strShow = strShow & " and #" & Format(dtTo.Value, "MM/dd/yyyy") & "# "
    strShow = strShow & " and B.IDNO = '" & Trim(txtCustomerId.Text) & "' "
    strShow = strShow & " and A.VREFNO = C.PurBillNo  "
    'strShow = strShow & " order by A.ID,A.DATED,A.VNO"
    rsShow.Open strShow, cn
    recCnt = rsShow("mCnt")
    rsShow.Close
    pgrPartyLedger.Max = recCnt + 1

    'VOUCHMST_P//VNO,DATED,VTYPE,REMARKS,byUser
    strShow = "select A.Id,A.cmnt,A.VNO,A.DATED,B.IDNO,B.IDNAME,B.AMOUNT,B.DR_CR,B.VNARRATION,A.REMARKS,C.DealInvNo, B.CQ_TYPE, B.BANKNAME, B.BANKBRANCH, B.CQ_NO from VOUCHMST A,VOUCHDAT B,mPurchase C "
    strShow = strShow & " where A.VNO=B.VNO and (A.REMARKS='CASH PURCHASE RETURN' OR A.REMARKS='CREDIT PURCHASE RETURN' OR A.REMARKS='CREDIT PURCHASE' OR A.REMARKS='CASH PURCHASE' OR A.REMARKS='PAYMENT' OR A.REMARKS='CREDIT NOTE') "
    strShow = strShow & " and A.DATED between #" & Format(dtFrom.Value, "MM/dd/yyyy") & "# "
    strShow = strShow & " and #" & Format(dtTo.Value, "MM/dd/yyyy") & "# "
    strShow = strShow & " and B.IDNO = '" & Trim(txtCustomerId.Text) & "' "
     strShow = strShow & " and A.VREFNO = C.PurBillNo  "
    strShow = strShow & " order by A.ID,A.DATED,A.VNO"
    rsShow.Open strShow, cn

    Dim mPur, mPayRet, mAnyAdv, mTempVNO
    mPur = 0
    mPayRet = 0
    mAnyAdv = 0

    mSlNo = 1
    ShowPaymentHeader
    Do While Not rsShow.EOF
        mTempVNO = rsShow("VNO")

        Set NewItem = listViewPayment.ListItems.Add(, "C" & mSlNo, Format(rsShow("DATED"), "dd/MM/yyyy"))
        NewItem.SubItems(1) = rsShow("VNO")
        NewItem.SubItems(13) = rsShow("DealInvNo")

        NewItem.SubItems(2) = IIf(IsNull(rsShow("IDNAME")), "", CommaFilterText(rsShow("IDNAME"), 1))
        If Trim(rsShow("REMARKS")) = "CASH PURCHASE" Then
            NewItem.SubItems(3) = FormatTakaPaisa(rsShow("AMOUNT"))
            NewItem.SubItems(4) = FormatTakaPaisa(rsShow("AMOUNT"))
        ElseIf Trim(rsShow("REMARKS")) = "CREDIT PURCHASE" Then
            mAnyAdv = ShowPartialAdvance(rsShow("VNO"))
            NewItem.SubItems(3) = FormatTakaPaisa(rsShow("AMOUNT") + Val(mAnyAdv))
            If Val(mAnyAdv) > 0 Then
                NewItem.SubItems(4) = FormatTakaPaisa(mAnyAdv)
            Else
                NewItem.SubItems(4) = ""
            End If
        Else
            NewItem.SubItems(3) = ""
            NewItem.SubItems(4) = FormatTakaPaisa(rsShow("AMOUNT"))
            NewItem.SubItems(7) = rsShow("CQ_TYPE")
            NewItem.SubItems(8) = rsShow("BANKNAME")
            NewItem.SubItems(9) = rsShow("BANKBRANCH")

            **    
            > NewItem.SubItems(9) = rsShow("cmnt")

            **

        End If
        NewItem.SubItems(6) = rsShow("IDNO")

        mPur = mPur + Val(NewItem.SubItems(3))
        mPayRet = mPayRet + Val(NewItem.SubItems(4))

        NewItem.SubItems(5) = rsShow("REMARKS")
        NewItem.SubItems(12) = GetVoucherRefNo(mTempVNO)

        pgrPartyLedger.Value = mSlNo

        mSlNo = mSlNo + 1
        rsShow.MoveNext
    Loop
    rsShow.Close

    lblTotPur.Caption = FormatTakaPaisa(mPur)
    lblTotPayRet.Caption = FormatTakaPaisa(mPayRet)
    lblBalance.Caption = FormatTakaPaisa(mPur - mPayRet)
    pgrPartyLedger.Value = 0        
End Sub

我收到该行的类型不匹配运行时错误 13，请帮助我

Answer 1

根据您的数据库设计和查询，您可能有具有空值的字段或具有零长度字符串的字段。 您应该始终检查这一点，尤其是在执行外部联接或查询中的多个联接时。

如果您仅检查一个表的内容并且您看到所有字段都已填充，这并不意味着结果集将仅返回有效值 - 但这超出了此答案的范围。

在处理 Recordset 时，检查字段值和捕获错误有多种常见做法。仅举几例：

1. On Error Resume ... 块：避免这个，你没有概述 发生了什么

2. 检查Null 值、DBNull 值、Empty 值或检查Field Type。只有一个 示例：

   If IsNull(rsShow("cmnt").value) = True Then NewItem.SubItems(9) = "" Else NewItem.SubItems(9) = rsShow("cmnt") End If

   注意：您应该明确该字段的value 属性。

   如果你做字段类型检查，学习使用集成在 VB IDE 中的对象浏览器，这将是你最好的朋友。

3. 检查字段的ActualSize 属性：参见MSDN：The Field Object

4. 另一种常见的快捷方式是在字段的返回值前添加或附加长度为零的字符串，这仅在您不必区分 Null 值和 Blank 值时才有效而且您只需要在标签或列表中显示结果，因为您的情况是： NewItem.SubItems(9) = "" & rsShow("cmnt")

关于Error 13：在VB IDE中，打开Immediate Window，输入：? 0 = ""，然后回车。结果如何？

最后但同样重要的是，始终仔细检查字段名称，每个数据库开发人员都曾因拼写错误而面临错误，尤其是在处理具有数十个表和数百个字段的金融应用程序时。