getelementsbytagname for xml response text not working

问题

I'm having trouble figuring out why my code isn't recognizing the tagname "HourlySchedule". When it gets to: For Each HourlySchedule In Resp.getElementsByTagName("HourlySchedule"), it will skip to the end instead of looping thru each tag. I've tried several different tag names and it doesn't seem to work. Any suggestions?

My VBA code:

    Sub Button1_Click()
    Dim URL As String: URL = "webaddress here"
    Dim mfile As String
    mfile = "<?xml version=" & """" & "1.0" & """" & "?><Envelope xmlns=" & """" & "http://schemas.xmlsoap.org/soap/envelope/" & """" & "><Header/><Body><QueryRequest xmlns=" & """" & "http://markets.midwestiso.org/dar/xml" & """" & "><QueryMarketResults day=" & """" & "2017-03-05" & """" & "><LocationName>Rug</LocationName></QueryMarketResults></QueryRequest></Body></Envelope>"

    Set Req = New WinHttp.WinHttpRequest
    With Req
        .Open "POST", URL, False
        .SetClientCertificate "CURRENT_USER\MY\name"
        .SetRequestHeader "content-type", "text/xml"
        .Send (mfile)
        .WaitForResponse
    End With

    Dim Resp As New MSXML2.DOMDocument60
    Resp.LoadXML Req.ResponseText

if Resp.loadxml (Req.ResponseText) then
   MsgBox "ok" else
   MsgBox "err"
end if

    Dim HourlySchedule As IXMLDOMNode
    For Each HourlySchedule In Resp.getElementsByTagName("HourlySchedule") ''this is where my problem is
    Debug.Print "test"
    Next HourlySchedule
    End Sub

Here is the xml i'm trying to parse:

<?xml version="1.0" encoding="UTF-8"?>
<Envelope xmlns="http://schemas.xmlsoap.org/soap/envelope/">
    <Body>
        <QueryResponse xmlns="http://markets.midwestiso.org/dart/xml">
            <MarketResults day="2017-03-05">
                <Location name="OTP.RUGBY1_IBR">
                    <HourlySchedule hour="1">
                        <ClearedEnergy MW="-6" virtualMW="0" price="7" capped="false"/>
                        <ClearedReg MW="0" price="10.18" capped="false"/>
                        <ClearedSpin MW="0" price="1" capped="false"/>
                        <ClearedSupp MW="0" price="0.5" capped="false"/>
                        <ClearedRampCapabilityUp MW="0" price="0"/>
                        <ClearedRampCapabilityDown MW="0" price="0"/>
                    </HourlySchedule>
                    <HourlySchedule hour="2">
                        <ClearedEnergy MW="-2" virtualMW="0" price="5.3" capped="false"/>
                        <ClearedReg MW="0" price="8.06" capped="false"/>
                        <ClearedSpin MW="0" price="1" capped="false"/>
                        <ClearedSupp MW="0" price="0.5" capped="false"/>
                        <ClearedRampCapabilityUp MW="0" price="0"/>
                        <ClearedRampCapabilityDown MW="0" price="0"/>
                    </HourlySchedule>
                </Location>
            </MarketResults>
        </QueryResponse>
    </Body>
</Envelope>

回答1:

An often cited issue in parsing XML documents is an undeclared namespace prefix which your response contains twice at different node levels. Notice no colon separated name is included which is a perfectly valid XML:

<Envelope xmlns="http://schemas.xmlsoap.org/soap/envelope/">

<QueryResponse xmlns="http://markets.midwestiso.org/dart/xml">

As a result, in VBA declare such namespaces by designating user-defined prefixes, here doc and doc2 is used. Then, using SelectNodes method over getElementsByTagName since you will need to reference the second defined prefix as HourlySchedule is a child of Query node, you can then query to the needed element:

...
   Dim HourlySchedule As IXMLDOMNode    
   Dim XmlNamespaces As String

   ' SPACE SEPARATED STRING
   XmlNamespaces = "xmlns:doc='http://schemas.xmlsoap.org/soap/envelope/'" _
                   & " xmlns:doc2='http://markets.midwestiso.org/dart/xml'"
   Resp.setProperty "SelectionNamespaces", XmlNamespaces

   For Each HourlySchedule In Resp.DocumentElement.SelectNodes("//doc2:HourlySchedule")
       Debug.Print "test"
   Next HourlySchedule

   Set Resp = Nothing 

End Sub

Output (in Immediate Window)

test
test

来源：https://stackoverflow.com/questions/44194763/getelementsbytagname-for-xml-response-text-not-working

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