Excel VBA - XML DomDocument return 属性值

Question

我正在处理 Excel VBA 中的以下 XML 响应。

<XXXXX docType="GetSegmentSpeed" copyright="Copyright XXXXX Inc." versionNumber="12.9" createdDate="2018-11-26T15:08:37Z" statusId="0" statusText="" responseId="06d3aad3-c3aa-40a5-9d2c-f1ac8f713729">
   <SegmentSpeedResultSet coverage="255">
      <SegmentSpeedResults timestamp="2018-11-26T15:08:36Z">
         <Segment code="213423027" type="XDS" speed="53" average="34" reference="40" score="30" c-value="63" travelTimeMinutes="0.649" speedBucket="3"/>
         <Segment code="213423023" type="XDS" speed="53" average="38" reference="41" score="30" c-value="58" travelTimeMinutes="0.603" speedBucket="3"/>
         <Segment code="213423026" type="XDS" speed="52" average="34" reference="39" score="30" c-value="71" travelTimeMinutes="0.486" speedBucket="3"/>
         <Segment code="213423050" type="XDS" speed="52" average="34" reference="39" score="30" c-value="71" travelTimeMinutes="0.48" speedBucket="3"/>
         <Segment code="213423051" type="XDS" speed="52" average="35" reference="39" score="30" c-value="78" travelTimeMinutes="0.486" speedBucket="3"/>
      </SegmentSpeedResults>
   </SegmentSpeedResultSet>
</XXXXX>

我想找到 Segments 的 travelTimeMinutes 属性的总数。

首先，我想我会尝试获取第一段的值。这是我的代码：

Sub SegSetTimes()

   ' Declare Private Variables
   Dim SegString As String 'Segment set to be used for calculation
   Dim hReq As New WinHttpRequest 'HttpRequest path
   Dim strResp As String 'Response String
   Dim xmlDoc As MSXML2.DOMDocument60 'DomDocument for parsing XML

   ' Import Segment Set
   SegString = Join(WorksheetFunction.Transpose(Range("A2", Range("A2").End(xlDown)).Value), "|XDS,")

   ' Call for real-time segment information
   hReq.Open "Get", "http://eu.api.XXXXX.com/Traffic/XXXXX.ashx?Action=GetSegmentSpeed" & "&token=" & AuthToken & "&Segments=" & SegString
   hReq.Send
   ' Create string from response text
   strResp = hReq.ResponseText

   ' Import response text into DomDocument for parsing within VBA
   Set xmlDoc = New MSXML2.DOMDocument60
   If Not xmlDoc.LoadXML(strResp) Then
      MsgBox "Load Error"
   End If

   Dim n As IXMLDOMNodeList
   Set n = xmlDoc.SelectNodes("//XXXXX/SegmentSpeedResultSet/SegmentSpeedResults")

   Dim TT As Single
   TT = n.Item(0).Attributes.getNamedItem("travelTimeMinutes")

End Sub

失败并出现以下错误：

Run-time error '91': Object variable or With block variable not set'

在 Locals 中单步执行时，我的 IXMLDOMNodeList n 看起来是正确的。我只是看不出如何获得我想要的值。

有人有什么建议吗？

Answer 1

从文件中读取我使用 XPath 获取相关节点，然后使用 getAttribute

提取值

Public Sub testing()
    Dim xmlDoc As New MSXML2.DOMDocument60, items As Object, item As IXMLDOMElement, total As Double
    Set xmlDoc = New MSXML2.DOMDocument60
    xmlDoc.Load "C:\Users\User\Desktop\Test.xml"
    Set items = xmlDoc.SelectNodes("//Segment[@travelTimeMinutes]")
    For Each item In items
        total = total + item.getAttribute("travelTimeMinutes")
    Next
    Debug.Print total
End Sub

Answer 2

或者，考虑运行 XSLT 在所有节点上检索 sum() 而无需循环：

XSLT (另存为.xsl文件，特殊的.xml文件，在VBA中引用)

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  <xsl:output indent="yes"/>
  <xsl:strip-space elements="*"/>

  <xsl:template match="/XXXXX">
    <result>
      <xsl:value-of select="format-number(sum(descendant::Segment/@travelTimeMinutes), '#.###')"/>
    </result>
  </xsl:template>

</xsl:stylesheet>

XSLT Demo

VBA

Dim xmlDoc As New MSXML2.DOMDocument60, items As Object, item As IXMLDOMElement, total As Double
' NEW REFERENCES    
Dim xslDoc As New MSXML2.DOMDocument60, newDoc As New MSXML2.DOMDocument60

' RETRIEVE WEB REQUEST   
...same code as above...

' LOAD XML AND XSL FILES 
xmlDoc.async = False
xml.LoadXML strResp

xslDoc.async = False
xslDoc.Load "C:\Path\to\XSLT\File.xsl"

' TRANSFORM XML
xmlDoc.transformNodeToObject xslDoc, newDoc

' OUTPUT RESULT (NO LOOPING)
Debug.Print newDoc.SelectSingleNode("/result").Text
' 2.704

Excel VBA - XML DomDocument return 属性值

Excel VBA - XML DomDocument return attribute values

xml

excel

vba

domdocument