VB.Net Xml Deserialization into a Class

Question

I have a bit of an issue trying to deserialize some XML into a class that I have created.

The error I get is:

There is an error in XML document (1, 2).

   at System.Xml.Serialization.XmlSerializer.Deserialize(XmlReader xmlReader, String encodingStyle, XmlDeserializationEvents events)
   at System.Xml.Serialization.XmlSerializer.Deserialize(TextReader textReader)
   at CommonLayer.InvuManager.FindDocuments(String policy, String year) in C:\GIT\novus\CommonLayer\InvuManager.vb:line 194
   at Novus.NavigationControlRisk.UpdateInvuDocumentsFolderTitle(TreeListNode& documentsFolderNode, String policy, String year) in C:\GIT\novus\Dashboard\src\Dashboard\NavigationControls\NavigationControlRisk.vb:line 3125
   at Novus.NavigationControlRisk.PopulateFolders(TreeListNode parentNode, Boolean isAttachingPolicy, Boolean refreshData) in C:\GIT\novus\Dashboard\src\Dashboard\NavigationControls\NavigationControlRisk.vb:line 1280
   at Novus.NavigationControlRisk.PopulateNode(Boolean refreshData) in C:\GIT\novus\Dashboard\src\Dashboard\NavigationControls\NavigationControlRisk.vb:line 1158
   at Novus.NavigationControlRisk.mainTreeList_MouseClick(Object sender, MouseEventArgs e, Boolean refreshData) in C:\GIT\novus\Dashboard\src\Dashboard\NavigationControls\NavigationControlRisk.vb:line 2340
   at Novus.NavigationControlRisk._Lambda$__R25-1(Object a0, MouseEventArgs a1)
   at System.Windows.Forms.Control.OnMouseClick(MouseEventArgs e)
   at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
   at System.Windows.Forms.Control.WndProc(Message& m)
   at DevExpress.XtraEditors.Container.EditorContainer.WndProc(Message& m)
   at DevExpress.XtraTreeList.TreeList.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
   at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
   at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(IntPtr dwComponentID, Int32 reason, Int32 pvLoopData)
   at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
   at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
   at Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.OnRun()
   at Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.DoApplicationModel()
   at Microsoft.VisualBasic.ApplicationServices.WindowsFormsApplicationBase.Run(String[] commandLine)
   at Novus.My.MyApplication.Main(String[] Args) in :line 81
   at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
   at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
   at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()

Here is the class I created, it's nothing fancy at this point, I'm simply trying to get it to work:

Imports System.Xml.Serialization

<Serializable, XmlRoot("Document")> _
Public Class Document
    <XmlElement("Type")> _
    Public Property Type As String
    <XmlElement("FileName")> _
    Public Property FileName As String
End Class

And here is the XML from the file I am using:

<ArrayOfDocuments>
  <Document>
    <Type>Debit/Credit note</Type>
    <FileName>dbE12901_acc1.doc</FileName>
  </Document>
  <Document>
    <Type>Generic</Type>
    <FileName>a3_lmbc_categories.xls</FileName>
  </Document>
</ArrayOfDocuments>

Finally, here is the code I am using:

Dim foundDocuments As New List(Of Document)
Dim xmldoc As New XmlDocument
xmldoc.Load(InterfaceFilePath)
Dim allText As String = xmldoc.InnerXml

Using currentStringReader As New StringReader(allText)
   Dim xml as New XmlSerializer(GetType(List(Of Document)))
   foundDocuments = TryCast(xml.Deserialize(currentStringReader), List(Of Document))
End Using

I cannot, for the life of me, figure out why it will not deserialize. I have other instances of different classes in my app and I have checked and the way they are structured is the same, so I do not understand why it will not work.

I need another pair of eyes just to check what I have done, does anyone have any suggestions?

Answer 1

You can automatically generate the class from xml by copying the xml text then in visual studio:

Edit >> Paste Special >> Paste XML As Classes

I did this and it yielded the classes

<System.Xml.Serialization.XmlTypeAttribute(AnonymousType:=True), _
 System.Xml.Serialization.XmlRootAttribute([Namespace]:="", IsNullable:=False)> _
Partial Public Class ArrayOfDocuments
    Private documentField() As ArrayOfDocumentsDocument
    <System.Xml.Serialization.XmlElementAttribute("Document")> _
    Public Property Document() As ArrayOfDocumentsDocument()
        Get
            Return Me.documentField
        End Get
        Set(value As ArrayOfDocumentsDocument())
            Me.documentField = value
        End Set
    End Property
End Class

<System.Xml.Serialization.XmlTypeAttribute(AnonymousType:=True)> _
Partial Public Class ArrayOfDocumentsDocument
    Private typeField As String
    Private fileNameField As String
    Public Property Type() As String
        Get
            Return Me.typeField
        End Get
        Set(value As String)
            Me.typeField = value
        End Set
    End Property
    Public Property FileName() As String
        Get
            Return Me.fileNameField
        End Get
        Set(value As String)
            Me.fileNameField = value
        End Set
    End Property
End Class

(Changed automatic name ArrayOfDocumentDocument to Document manually)

This is deserialized easily

Imports System.Xml.Serialization
Imports System.IO

---

Dim s As New XmlSerializer(GetType(ArrayOfDocuments))
Dim m As ArrayOfDocuments
Using sr As New StreamReader("XMLFile1.xml")
    m = s.Deserialize(sr)
End Using
Dim foundDocuments = m.Document.ToList()