VBA-Zugriff: XML Error '91': Objektvariable oder With-Blockvariable nicht festgelegt?

Nun, die Schule ist aus für den Sommer und ich habe einige freie Zeit, die ich gewählt haben, erstellen Sie ein persönliches Buch, das Inventar-system. Während der recherche stieß ich auf diesen Beitrag von Jules: ISBN -> bookdata-Lookup für das füllen der Datenbank

Wenn Sie versuchen, zu implementieren meinen code unten, habe ich zum ersten mal eine Run-time error: Access is denied bei der Verwendung Set xmlhttp = CreateObject("MSXML2.xmlhttp"). Ich fand den post (http://social.msdn.microsoft.com/Forums/en-US/1abda1ce-e23c-4d0e-bccd-a323aa7f2ea5/access-is-denied-while-using-microsoftxmlhttp-to-get-a-url-link-in-vbscript-help) sagte, dass die Linie wechseln, um Set xmlhttp = CreateObject("MSXML2.ServerXMLHTTP.6.0").

Ich jetzt erhalte Run-time error '91': Object variable or With block variable not set.

Jemand irgendwelche Ideen, wie man dieses Problem beheben? Ich bin neu in der Arbeit mit XML. Zum testen bin ich mit der Immediate-Fenster und die Eingabe von testlookup("0007102968").

Modul SearchISBN:

Option Compare Database
Option Explicit

Public Function testlookup(value As String)
    Dim book
    Set book = New isbn
    book.Lookup (value)
    Debug.Print book.Title
    Debug.Print book.PublisherText
End Function

Klassenmodul isbn:

Option Compare Database
Option Explicit

'https://stackoverflow.com/questions/2454348/isbn-bookdata-lookup-to-fill-in-a-database
' AccessKeys created with account on ISBNDB.com
' Reference in (Tools->Refernces) made to "Microsoft XML"

Dim strTitle As String
Dim strAuthor As String
Dim strPublisher As String
Dim strSummary As String
Dim strPrice As Currency
Dim strISBN10 As Integer
Dim strISBN13 As Integer
Dim strNotes As String
'Dim strPersRating As String
Dim accessKey As String

Private Sub Class_Initialize()
    ' Set AccessKey value of ISBNDB API
    accessKey = "NSOY388Z"
End Sub
Property Get Title() As String
    Title = strTitle
End Property
Property Get Author() As String
    Author = strAuthor
End Property
Property Get Publisher() As String
    Publisher = strPublisher
End Property
Property Get Summary() As String
    Summary = strSummary
End Property
Property Get Price() As Currency
    Price = strPrice
End Property
Property Get ISBN10() As Integer
    ISBN10 = strISBN10
End Property
Property Get ISBN13() As Integer
    ISBN13 = strISBN13
End Property
Property Get Notes() As String
    Notes = strNotes
End Property

Public Function Lookup(isbn As String) As Boolean
    Lookup = False
'    Dim xmlhttp
'    Dim strTest As String
'    strTest = "https://isbndb.com/api/books.xml?access_key=" & accessKey & "&results=texts&index1=isbn&value1=" & isbn
'    Debug.Print strTest
'    'Run-time error, access is denied
'    ' Set xmlhttp = CreateObject("MSXML2.xmlhttp")
'    Set xmlhttp = CreateObject("MSXML2.ServerXMLHTTP.6.0")
'    xmlhttp.Open "Get", strTest, False '"https://isbndb.com/api/books.xml?access_key=" & accessKey & "&results=texts&index1=isbn&value1=" & isbn, False
'    xmlhttp.send
'    Debug.Print xmlhttp.responseText
'    Debug.Print "Response: " & xmlhttp.responseXML.XML '
'    Dim xmldoc
''    Set xmldoc = CreateObject("Microsoft.XMLDOM")
''    xmldoc.loadXML (xmlhttp.responseXML.XML)
''    ERROR
''    If (xmldoc.selectSingleNode("//BookList").getAttribute("total_results") = 0) Then
''        MsgBox "Invalid ISBN or not in database"
''        Exit Function
''    End If
''    If (xmldoc.selectSingleNode("//BookList").getAttribute("total_results") > 1) Then
''        MsgBox "Caution, got more than one result!"
''        Exit Function
''    End If
'
'    Set xmldoc = New DOMDocument
'    xmldoc.loadXML (xmlhttp.responseText)
'
'
'
'    strTitle = xmldoc.selectSingleNode("//BookData/TitleLong").Text
'    strAuthor = xmldoc.selectSingleNode("//BookData/AuthorsText").Text
'    strPublisher = xmldoc.selectSingleNode("//BookData/PublisherText").Text
'    strNotes = xmldoc.selectSingleNode("//BookData/Notes").Text
'    strSummary = xmldoc.selectSingleNode("//BookData/Summary").Text
'

    Dim xmlhttp As MSXML2.xmlhttp
    Dim xmldoc As MSXML2.DOMDocument
    Dim XMLNodes As MSXML2.IXMLDOMNodeList
    Dim xmlElement As MSXML2.IXMLDOMElement
    Dim bookTitle As String
    Dim myErr As MSXML2.IXMLDOMParseError

    Dim strTest As String
    strTest = "https://isbndb.com/api/books.xml?access_key=" & accessKey & "&results=texts&index1=isbn&value1=" & isbn

    ' Fetch the XML - THIS IS WHERE I AM NOW GETTING ERROR
    xmlhttp.Open "Get", strTest, False '"https://isbndb.com/api/books.xml?access_key=" & accessKey & "&results=texts&index1=isbn&value1=" & isbn, False
    xmlhttp.send

    Set xmldoc = New DOMDocument
    xmldoc.loadXML (xmlhttp.responseText)

    Set XMLNodes = xmldoc.getElementsByTagName("BookData")

    Dim i As Integer

    ' Get the data
    For i = 1 To XMLNodes.length
        Set xmlElement = XMLNodes.nextNode
        bookTitle = xmlElement.getElementsByTagName("Title").Item(0).nodeTypedValue
    Next

    Lookup = True

End Function

BEARBEITEN: Noch immer die Fehler, aber bin jetzt immer eine Antwort im Direktfenster:

https://isbndb.com/api/books.xml?access_key=NSOY388Z&results=texts&index1=isbn&value1=0007102968
Response: 
<?xml version="1.0" encoding="UTF-8"?>

<ISBNdb server_time="2013-06-20T16:20:00Z">
<BookList total_results="1" page_size="10" page_number="1" shown_results="1">
<BookData book_id="the_times_book_of_quotations" isbn="0007102968" isbn13="9780007102969">
<Title>The Times book of quotations</Title>
<TitleLong></TitleLong>
<AuthorsText></AuthorsText>
<PublisherText publisher_id="times_books">[Glasgow] : Times Books : 2000.</PublisherText>
<Summary></Summary>
<Notes>Includes index.</Notes>
<UrlsText></UrlsText>
<AwardsText></AwardsText>
</BookData>
</BookList>
</ISBNdb>

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