一个可能的（工作）解决方案：

Question

一个可能的（工作）解决方案：

Private Sub ReadXMLAttributes(ByVal oXML As String)
    ReadXMLAttributes(oXML, "mso-infoPathSolution")
End Sub
Private Sub ReadXMLAttributes(ByVal oXML As String, ByVal oTagName As String)
    Try
        Dim XmlDoc As New Xml.XmlDocument
        XmlDoc.LoadXml(oXML)
        oFileInfo = New InfoPathDocument
        Dim XmlNodes As Xml.XmlNodeList = XmlDoc.GetElementsByTagName(oTagName)
        For Each xNode As Xml.XmlNode In XmlNodes
            With xNode
                oFileInfo.SolutionVersion = .Attributes(InfoPathSolution.solutionVersion).Value
                oFileInfo.ProductVersion = .Attributes(InfoPathSolution.productVersion).Value
                oFileInfo.PIVersion = .Attributes(InfoPathSolution.PIVersion).Value
                oFileInfo.href = .Attributes(InfoPathSolution.href).Value
                oFileInfo.name = .Attributes(InfoPathSolution.name).Value
            End With
        Next
    Catch ex As Exception
        MsgBox(ex.Message, MsgBoxStyle.OkOnly, "ReadXMLAttributes")
    End Try
End Sub

这样可行，但如果重新排序属性，它仍会遇到下面的问题。我能想到避免这个问题的唯一方法是将属性名称硬编码到我的程序中，让它通过循环解析标记并搜索指定的标记来处理条目。

注意：InfoPathDocument是我制作的自定义类，它并不复杂：

Public Class InfoPathDocument
    Private _sVersion As String
    Private _pVersion As String
    Private _piVersion As String
    Private _href As String
    Private _name As String
    Public Property SolutionVersion() As String
        Get
            Return _sVersion
        End Get
        Set(ByVal value As String)
            _sVersion = value
        End Set
    End Property
    Public Property ProductVersion() As String
        Get
            Return _pVersion
        End Get
        Set(ByVal value As String)
            _pVersion = value
        End Set
    End Property
    Public Property PIVersion() As String
        Get
            Return _piVersion
        End Get
        Set(ByVal value As String)
            _piVersion = value
        End Set
    End Property
    Public Property href() As String
        Get
            Return _href
        End Get
        Set(ByVal value As String)
            If value.ToLower.StartsWith("file:///") Then
                value = value.Substring(8)
            End If
            _href = Form1.PathToUNC(URLDecode(value))
        End Set
    End Property
    Public Property name() As String
        Get
            Return _name
        End Get
        Set(ByVal value As String)
            _name = value
        End Set
    End Property
    Sub New()

    End Sub
    Sub New(ByVal oSolutionVersion As String, ByVal oProductVersion As String, ByVal oPIVersion As String, ByVal oHref As String, ByVal oName As String)
        SolutionVersion = oSolutionVersion
        ProductVersion = oProductVersion
        PIVersion = oPIVersion
        href = oHref
        name = oName
    End Sub
    Public Function URLDecode(ByVal StringToDecode As String) As String
        Dim TempAns As String = String.Empty
        Dim CurChr As Integer = 1
        Dim oRet As String = String.Empty
        Try
            Do Until CurChr - 1 = Len(StringToDecode)
                Select Case Mid(StringToDecode, CurChr, 1)
                    Case "+"
                        oRet &= " "
                    Case "%"
                        oRet &= Chr(Val("&h" & Mid(StringToDecode, CurChr + 1, 2)))
                        CurChr = CurChr + 2
                    Case Else
                        oRet &= Mid(StringToDecode, CurChr, 1)
                End Select
                CurChr += 1
            Loop
        Catch ex As Exception
            MsgBox(ex.Message, MsgBoxStyle.OkOnly, "URLDecode")
        End Try
        Return oRet
    End Function
End Class

原始问题

我正在开发一个需要读取XML文档的项目，特别是Microsoft InfoPath中保存的表单。

以下是我将要使用的一个简单示例以及可能有用的一些背景信息：

<?xml version="1.0" encoding="UTF-8"?>
<?mso-infoPathSolution solutionVersion="1.0.0.2" productVersion="12.0.0" PIVersion="1.0.0.0" href="file:///C:\Users\darren\Desktop\simple_form.xsn" name="urn:schemas-microsoft-com:office:infopath:simple-form:-myXSD-2009-05-15T14-16-37" ?>
<?mso-application progid="InfoPath.Document" versionProgid="InfoPath.Document.2"?>
<my:myFields xmlns:my="http://schemas.microsoft.com/office/infopath/2003/myXSD/2009-05-15T14:16:37" xml:lang="en-us">
    <my:first_name>John</my:first_name>
    <my:last_name>Doe</my:last_name>
</my:myFields>

我现在的目标是提取表单的versionID和位置。正则表达式很容易：

Dim _doc As New XmlDocument
_doc.Load(_thefile)
Dim oRegex As String = "^solutionVersion=""(?<sVersion>[0-9.]*)"" productVersion=""(?<pVersion>[0-9.]*)"" PIVersion=""(?<piVersion>[0-9.]*)"" href=""(?<href>.*)"" name=""(?<name>.*)""$"
Dim rx As New Regex(oRegex), m As Match = Nothing
For Each section As XmlNode In _doc.ChildNodes
    m = rx.Match(section.InnerText.Trim)
    If m.Success Then
        Dim temp As String = m.Groups("name").Value.Substring(m.Groups("name").Value.ToLower.IndexOf("infopath") + ("infopath").Length + 1)
        fileName = temp.Substring(0, temp.LastIndexOf(":"))
        fileVersion = m.Groups("sVersion").Value
    End If
Next

这个工作解决方案带来的唯一问题是，如果InfoPath文档标题中的架构发生了变化......例如解决方案版本和产品版本属性交换位置（微软LOVES做这样的事情，似乎）。

所以我选择尝试使用VB.NET的XML解析功能来帮助我实现上述结果，sans-regex。

包含我需要的信息的ChildNode对象中的_doc，但它没有任何ChildNodes：

_doc.ChildNode(1).HasChildNodes = False

任何人都可以帮我解决这个问题吗？

Answer 1

处理指令是XML文档的一部分，但它们的属性不会被解析。试试这段代码：

// Load the original xml...
var xml = new XmlDocument();
xml.Load( _thefile );

// Select out the processing instruction...
var infopathProcessingInstruction = xml.SelectSingleNode( "/processing-instruction()[local-name(.) = \"mso-infoPathSolution\"]" );

// Since the processing instruction does not expose it's attributes, create a new XML document...
var xmlInfoPath = new XmlDocument();
xmlInfoPath.LoadXml("<data " + infopathProcessingInstruction.InnerText + " />");

// Get the data...
var solutionVersion = xmlInfoPath.DocumentElement.GetAttribute("solutionVersion");
var productVersion  = xmlInfoPath.DocumentElement.GetAttribute("productVersion");

Answer 2

问题是您要解析的标签实际上不是XML文档的一部分。它们是包含处理指令的XML-Prolog。因此它们不会作为元素在XmlDocument中可用。

在剥离＆lt ;?之后，我唯一的想法是（除了查看文档如何访问这些元素之外）将mso-infoPathSolution-element移动到它自己的XmlDocument中。？＆GT;离开并用＆lt;替换它们/取代。然后，您可以访问属性，无论其顺序如何。

在VB.NET中读取XML标记信息

一个可能的（工作）解决方案：

原始问题

2 个答案: