Lambda参数'<parameter>'隐藏了一个封闭块</parameter>中的变量

时间:2013-09-03 11:56:43

标签: vb.net closures

在运行vb.net时......编码工作正常,我得到的输出低于错误...

  

Lambda参数'{parameter}'隐藏封闭块中的变量,先前定义的范围变量或查询表达式中隐式声明的变量。

如何解决此错误?

以下是代码:

Private Sub ButtonProductAdvertisingAPIItemLookup_Click(ByVal sender As System.Object,ByVal e As System.EventArgs)Handles ButtonProductAdvertisingAPIItemLookup.Click         sender.Enabled = False

    'Product Advertising API, ItemLookup: http://docs.aws.amazon.com/AWSECommerceService/2011-08-01/DG/ItemLookup.html

    Dim ItemId(9) As String

    ItemId(0) = System.Uri.EscapeDataString(TextBoxisbn1.Text)
    ItemId(1) = System.Uri.EscapeDataString(TextBoxisbn2.Text)
    ItemId(2) = System.Uri.EscapeDataString(TextBoxisbn3.Text)
    ItemId(3) = System.Uri.EscapeDataString(TextBoxisbn4.Text)
    ItemId(4) = System.Uri.EscapeDataString(TextBoxisbn5.Text)
    ItemId(5) = System.Uri.EscapeDataString(TextBoxisbn6.Text)
    ItemId(6) = System.Uri.EscapeDataString(TextBoxisbn7.Text)
    ItemId(7) = System.Uri.EscapeDataString(TextBoxisbn8.Text)
    ItemId(8) = System.Uri.EscapeDataString(TextBoxisbn9.Text)
    ItemId(9) = System.Uri.EscapeDataString(TextBoxisbn10.Text)

    ' For Each ItemId As String In ItemIds()

    Dim i As Integer = 0
    System.Threading.Tasks.Parallel.ForEach(ItemIds, Sub(ItemId)

                                                         My.Settings.ItemId = ItemId

                                                         Dim MyREST As New SprightlySoftAWS.REST

                                                         Dim RequestURL(i) As String
                                                         RequestURL(i) = "https://webservices.amazon.com/onca/xml?Service=AWSECommerceService&Operation=ItemLookup&Version=2011-08-01"
                                                         RequestURL(i) += "&AWSAccessKeyId=AKIAJCA3UI55HFYAXQ6Q&SignatureVersion=2&SignatureMethod=HmacSHA256&Timestamp=" & Uri.EscapeDataString(DateTime.UtcNow.ToString("yyyy-MM-dd\THH:mm:ss.fff\Z"))
                                                         RequestURL(i) += "&AssociateTag=AKIAJCA3UI55HFYAXQ6Q"
                                                         RequestURL(i) += "&ResponseGroup=" & System.Uri.EscapeDataString("ItemAttributes,Large,OfferSummary,Offers,VariationSummary,Reviews")
                                                         RequestURL(i) += "&ItemId=" & System.Uri.EscapeDataString(ItemId)
                                                         RequestURL(i) += "&IdType=ISBN"
                                                         RequestURL(i) += "&SearchIndex=Books"

                                                         Dim RequestMethod As String
                                                         RequestMethod = "GET"

                                                         Dim SignatureValue As String
                                                         SignatureValue = MyREST.GetSignatureVersion2Value(RequestURL(i), RequestMethod, "", "8igixqKPKWTcsWxgWdqz+rVofSWIPcC3WynhEl1r")

                                                         RequestURL(i) += "&Signature=" & System.Uri.EscapeDataString(SignatureValue)

                                                         Dim RetBool As Boolean
                                                         RetBool = MyREST.MakeRequest(RequestURL(i), RequestMethod, Nothing)

                                                         Debug.Print("")
                                                         Debug.Print(MyREST.LogData)
                                                         Debug.Print("")

                                                         Dim Y As Integer
                                                         Dim ResponseMessage As String = ""

                                                         If RetBool = True Then
                                                             Dim MyXmlDocument As System.Xml.XmlDocument
                                                             Dim MyXmlNamespaceManager As System.Xml.XmlNamespaceManager
                                                             Dim MyXmlNode As System.Xml.XmlNode
                                                             Dim MyXmlNodeList As System.Xml.XmlNodeList

                                                             MyXmlDocument = New System.Xml.XmlDocument
                                                             MyXmlDocument.LoadXml(MyREST.ResponseString)

                                                             MyXmlNamespaceManager = New System.Xml.XmlNamespaceManager(MyXmlDocument.NameTable)
                                                             MyXmlNamespaceManager.AddNamespace("amz", "http://webservices.amazon.com/AWSECommerceService/2011-08-01")

                                                             MyXmlNodeList = MyXmlDocument.SelectNodes("amz:ItemLookupResponse/amz:Items/amz:Item", MyXmlNamespaceManager)

                                                             If MyXmlNodeList.Count = 0 Then
                                                                 ResponseMessage = "Item not found."
                                                             Else

                                                                 For Each ItemXmlNode As System.Xml.XmlNode In MyXmlNodeList
                                                                     MyXmlNode = ItemXmlNode.SelectSingleNode("amz:ASIN", MyXmlNamespaceManager)
                                                                     ResponseMessage += "Details of " & MyXmlNode.InnerText

                                                                     ResponseMessage += vbCrLf
                                                                     ResponseMessage += vbCrLf

                                                                     MyXmlNode = ItemXmlNode.SelectSingleNode("amz:ItemAttributes/amz:Title", MyXmlNamespaceManager)
                                                                     ResponseMessage += "Title = " & MyXmlNode.InnerText

                                                                     ResponseMessage += vbCrLf

                                                                     MyXmlNode = ItemXmlNode.SelectSingleNode("amz:MediumImage/amz:URL", MyXmlNamespaceManager)
                                                                     ResponseMessage += "Image = " & MyXmlNode.InnerText

                                                                     ResponseMessage += vbCrLf

                                                                     MyXmlNodeList = ItemXmlNode.SelectNodes("amz:ItemAttributes/amz:Author", MyXmlNamespaceManager)
                                                                     If IsNothing(MyXmlNodeList) = False Then
                                                                         ResponseMessage += "Author = "
                                                                         For Each MyXmlNode In MyXmlNodeList
                                                                             ResponseMessage += MyXmlNode.InnerText & ", "
                                                                         Next
                                                                     End If

                                                                     ResponseMessage += vbCrLf

                                                                     MyXmlNode = ItemXmlNode.SelectSingleNode("amz:ItemAttributes/amz:ListPrice/amz:FormattedPrice", MyXmlNamespaceManager)
                                                                     ResponseMessage += "ListPrice = "
                                                                     If IsNothing(MyXmlNode) = False Then
                                                                         ResponseMessage += MyXmlNode.InnerText
                                                                     End If

                                                                     ResponseMessage += vbCrLf

                                                                     MyXmlNode = ItemXmlNode.SelectSingleNode("amz:Offers/amz:Offer/amz:OfferAttributes/amz:Condition", MyXmlNamespaceManager)
                                                                     ResponseMessage += "Condition = " & MyXmlNode.InnerText

                                                                     ResponseMessage += vbCrLf

                                                                     MyXmlNode = ItemXmlNode.SelectSingleNode("amz:Offers/amz:TotalOffers", MyXmlNamespaceManager)
                                                                     ResponseMessage += "TotalOffers = " & MyXmlNode.InnerText

                                                                     ResponseMessage += vbCrLf

                                                                     MyXmlNode = ItemXmlNode.SelectSingleNode("amz:OfferSummary/amz:TotalNew", MyXmlNamespaceManager)
                                                                     ResponseMessage += "TotalNew = " & MyXmlNode.InnerText

                                                                     ResponseMessage += vbCrLf

                                                                     MyXmlNodeList = ItemXmlNode.SelectNodes("amz:OfferSummary/amz:LowestNewPrice/amz:FormattedPrice", MyXmlNamespaceManager)
                                                                     ResponseMessage += "LowestNewPrice = "
                                                                     Y = 0
                                                                     For Each MyXmlNode In MyXmlNodeList
                                                                         If Y < 25 Then
                                                                             ResponseMessage += "" & MyXmlNode.InnerText & "  "
                                                                         End If
                                                                     Next

                                                                     ResponseMessage += vbCrLf

                                                                     MyXmlNode = ItemXmlNode.SelectSingleNode("amz:OfferSummary/amz:TotalUsed", MyXmlNamespaceManager)
                                                                     ResponseMessage += "TotalUsed = " & MyXmlNode.InnerText

                                                                     ResponseMessage += vbCrLf

                                                                     MyXmlNode = ItemXmlNode.SelectSingleNode("amz:OfferSummary/amz:LowestUsedPrice/amz:FormattedPrice", MyXmlNamespaceManager)
                                                                     ResponseMessage += "LowestUsedPrice = "
                                                                     If IsNothing(MyXmlNode) = False Then
                                                                         ResponseMessage += "" & MyXmlNode.InnerText
                                                                     Else
                                                                         ResponseMessage += "0"
                                                                     End If

                                                                     ResponseMessage += vbCrLf

                                                                     'MyXmlNode = ItemXmlNode.SelectSingleNode("amz:SalesRank", MyXmlNamespaceManager)
                                                                     'ResponseMessage += "SalesRank = " & MyXmlNode.InnerText

                                                                     'ResponseMessage += vbCrLf
                                                                 Next
                                                             End If

                                                             DialogOutput.Text = "Success"
                                                             DialogOutput.TextBoxOutput.Text += vbCrLf & ResponseMessage & vbCrLf


                                                         Else
                                                             ResponseMessage = FormatLogData(MyREST.RequestURL, MyREST.RequestMethod, MyREST.RequestHeaders, MyREST.ResponseStatusCode, MyREST.ResponseStatusDescription, MyREST.ResponseHeaders, MyREST.ResponseStringFormatted, MyREST.ErrorNumber, MyREST.ErrorDescription)

                                                             DialogOutput.Text = "Error"
                                                             DialogOutput.TextBoxOutput.Text = ResponseMessage
                                                             DialogOutput.ShowDialog(Me)
                                                             DialogOutput.Dispose()
                                                         End If

                                                         i = i + 1
                                                     End Sub)
    'Next

    DialogOutput.ShowDialog(Me)
    ClearTextBox(Me)
    sender.Enabled = True
End Sub

错误显示在下面的行中(错误显示在ItemId变量中):

System.Threading.Tasks.Parallel.ForEach(ItemIds, Sub(ItemId)

我已经更新了额外的代码。任何人检查并帮助我?如何解决这个问题?我仍然得到错误..

1 个答案:

答案 0 :(得分:0)

鉴于所描述的错误,包括在评论中:

  1. 您已在外部例程中声明ItemId
  2. 您的ItemIdsIEnumerable(Of String()),或同等的。
  3. 以及其他一些评论:

    • 您的摘录不完整:您需要结束End Sub)
    • 您应该使用&=,就像您已经使用&进行连接一样。

    您的额外代码无助于解决您的问题,但它确实强调您需要进行更多审核。例如,您声明了一个i+1 RequestURL String的数组,然后只使用其中的最后一个,并且还注意这些是并行执行的{{1}实际发生时几乎可以是任何值。

    为了帮助解决您的问题,我们需要上面的代码。