Serialize multiple objects into a single XML File

[kumika]

I have a parent class with daughter and granddaughter classes. Now I want to XMLserialize all classes/objects in one code in order to generate, not one file for each object but, one file for all the objects. How do I do this? The posts I have read seem to have dead ends. I know how to serialize a single object but I need code to serialize all files at once into a single File. Good references are welcome. I use vb.net, but c# is also welcome. Thanks for assisting.

[techgnome]

if the daughter & grand daughter classes are members/properties of the parent class... and everything has been marked as serializable... then serializing the parent will serialize everything all the way down.

-tg

[kumika]

When I serialize the parent class I get an empty file with the Root element only. The records are actually in the daughter classes, which are initialized on Window.Loaded. I tried to serialize the parent class as follows:

 Dim pr  As  New parentClass
Dim Xm As New XmlSerializer(pr.GetType)
Dim tw As Textwriter = New StreamWriter(....filePath..)

Xm.Serialize(tw,pr)          
tw.Close

How and where do I access the daughter objects here? I get lost on that question. I only get data if I reference one daughter object at a time as: Dim pr As New daughterClassO1 and do the rest as above. Then the whole daughter class referenced is serialized fine. Please help.

[techgnome]

you serialized an empty object.... OF COURSE you're going to get an empty file...

You need to create your object, fill/populate it... then serialize it...

-tg

[kumika]

Would someone be kind enough to draft me an outline of how I can populate and serialize in a way that would generate the Xml file shown below: Take a look at the Class (shortened). Just do the header records. Thanks

Option Strict Off
Option Explicit On

Imports System.Xml.Serialization


'''<remarks/>
<System.CodeDom.Compiler.GeneratedCodeAttribute("xsd", "2.0.50727.1432"),  _
 System.SerializableAttribute(),  _
 System.Diagnostics.DebuggerStepThroughAttribute(),  _
 System.ComponentModel.DesignerCategoryAttribute("code"),  _
 System.Xml.Serialization.XmlTypeAttribute(AnonymousType:=true),  _
 System.Xml.Serialization.XmlRootAttribute([Namespace]:="", IsNullable:=false)>  _
Partial Public Class EducatorRegistration
    
    Private headerField As EducatorRegistrationHeader
    
    Private educatorInformationField() As EducatorRegistrationEducatorInformation
    
    Private trailerField As EducatorRegistrationTrailer
    
    '''<remarks/>
    Public Property Header() As EducatorRegistrationHeader
        Get
            Return Me.headerField
        End Get
        Set
            Me.headerField = value
        End Set
    End Property
    
    '''<remarks/>
    <System.Xml.Serialization.XmlElementAttribute("EducatorInformation")>  _
    Public Property EducatorInformation() As EducatorRegistrationEducatorInformation()
        Get
            Return Me.educatorInformationField
        End Get
        Set
            Me.educatorInformationField = value
        End Set
    End Property
    
    '''<remarks/>
    Public Property Trailer() As EducatorRegistrationTrailer
        Get
            Return Me.trailerField
        End Get
        Set
            Me.trailerField = value
        End Set
    End Property
End Class

'''<remarks/>
<System.CodeDom.Compiler.GeneratedCodeAttribute("xsd", "2.0.50727.1432"),  _
 System.SerializableAttribute(),  _
 System.Diagnostics.DebuggerStepThroughAttribute(),  _
 System.ComponentModel.DesignerCategoryAttribute("code"),  _
 System.Xml.Serialization.XmlTypeAttribute(AnonymousType:=true)>  _
Partial Public Class EducatorRegistrationHeader
    
    Private recordField As EducatorRegistrationHeaderRecord
    
    '''<remarks/>
    Public Property Record() As EducatorRegistrationHeaderRecord
        Get
            Return Me.recordField
        End Get
        Set
            Me.recordField = value
        End Set
    End Property
End Class

'''<remarks/>
<System.CodeDom.Compiler.GeneratedCodeAttribute("xsd", "2.0.50727.1432"),  _
 System.SerializableAttribute(),  _
 System.Diagnostics.DebuggerStepThroughAttribute(),  _
 System.ComponentModel.DesignerCategoryAttribute("code"),  _
 System.Xml.Serialization.XmlTypeAttribute(AnonymousType:=true)>  _
Partial Public Class EducatorRegistrationHeaderRecord
    
    Private filenameField As String
    
    Private provinceIDField As String
    
    Private emisNumberField As String
    
    Private statusIDField As String
    
    Private transactionCategoryIDField As String
    
    Private sequenceNumberField As String
    
    Private dateCreatedField As Date
    
    Private createdByField As String
    
    Private typeField As Byte
    
    '''<remarks/>


....................
PROPERTY ACCESORS
..................


End Class

""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
  <?xml version="1.0" ?> 
- <EducatorRegistration xmlns="urn:educatorreg-schema">
- <Header>
- <Record type="1">
  <Filename>aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa</Filename> 
  <ProvinceID>5</ProvinceID> 
  <EmisNumber>500000006</EmisNumber> 
  <StatusID>1</StatusID> 
  <TransactionCategoryID>13</TransactionCategoryID> 
  <SequenceNumber>1</SequenceNumber> 
  <DateCreated>2007-08-12</DateCreated> 
  <CreatedBy>aaaffffyyyyrtrr</CreatedBy> 
  </Record>
  </Header>
- <EducatorInformation>
- <EducatorBiographical>
- <Record type="2">
  <ProvinceID>5</ProvinceID> 
  <EducatorNumber>XYZ507000001</EducatorNumber> 
  <EmisNumber>500000006</EmisNumber> 
  <TitleID>Mr</TitleID> 
  <EducatorFirstName>BBBB</EducatorFirstName> 
  <EducatorSecondName>BBBB</EducatorSecondName> 
  <EducatorSurname>AAAA</EducatorSurname> 
  <PersalNumber>CCCCC</PersalNumber> 
  <SACENumber>DDDDDD</SACENumber> 
  <GenderID>1</GenderID> 
  <PopulationGroupID>1</PopulationGroupID> 
  <BirthDate>20010212</BirthDate> 
  <EducatorTelephoneCode>021</EducatorTelephoneCode> 
  <EducatorTelephone>7881100</EducatorTelephone> 
  <EducatorCellphoneCode /> 
  <EducatorCellphone /> 
  <HomeLanguageID>2</HomeLanguageID> 
  <DisabilityStatusID>1</DisabilityStatusID> 
  <OtherDisability>Ahhhh</OtherDisability> 
  <DateRegistered>20070109</DateRegistered> 
  <PostLevelID>1</PostLevelID> 
  <YearsExperience /> 
  <ActualPositionID>1</ActualPositionID> 
  <ActingPositionID /> 
  <NatureAppointmentID>1</NatureAppointmentID> 
  <RemunerationID>1</RemunerationID> 
  <DurationID>1</DurationID> 
  <TeachingLevelID1>1</TeachingLevelID1> 
  <TeachingLevelID2 /> 
  <QualificationID /> 
  <REQVQualificationID>10</REQVQualificationID> 
  <LURITSEducatorID>0</LURITSEducatorID> 
  </Record>
  </EducatorBiographical>
- <EducatorSubject>
- <Record type="3">
  <EmisNumber>500000006</EmisNumber> 
  <EducatorNumber>508000001</EducatorNumber> 
  <Year>2007</Year> 
  <SubjectID>1</SubjectID> 
  <TeachingExperience>1</TeachingExperience> 
  <YearsFormalTraining>0</YearsFormalTraining> 
  <ExaminableID>1</ExaminableID> 
  </Record>
  </EducatorSubject>
- <EducatorClass>
- <Record type="4">
  <EmisNumber>500000006</EmisNumber> 
  <EducatorNumber>508000001</EducatorNumber> 
  <Year>2007</Year> 
  <SubjectID>1</SubjectID> 
  <GradeID>22</GradeID> 
  <Class>Penguins</Class> 
  <HoursPerWeek>03:30</HoursPerWeek> 
  <NumberLearners>10</NumberLearners> 
  </Record>
  </EducatorClass>
  </EducatorInformation>
- <Trailer>
- <Record type="9">
  <FileName /> 
  <NumberOfRecords>1</NumberOfRecords> 
  </Record>
  </Trailer>
  </EducatorRegistration>

[kumika]

I don't want to accept that this thread is too bit for all of us. There must be one or two brains that can crack this one. I personally have hit a brick wall. I just can't figure out how I can use the parent object to serialize data in the daughter objects. Please any help is welcome. Thanks.

[wild_bill]

Try this

    Sub Main()

        'get data from file
        Dim xmlData = IO.File.ReadAllText("C:\temp1\EducatorRegistration.xml")
        'create object from data
        Dim o = DeserializeFromString(xmlData)

    End Sub

    Private Function DeserializeFromString(ByVal input As String) As EducatorRegistration

        'Convert to byte array
        Dim encoding As New System.Text.UnicodeEncoding
        Dim bytes() As Byte = encoding.GetBytes(input)

        'read bytes into stream
        Dim ms As New System.IO.MemoryStream
        ms.Write(bytes, 0, bytes.Length)
        ms.Position = 0

        'get object from bytes
        Dim xs As New Xml.Serialization.XmlSerializer(GetType(EducatorRegistration))
        Return DirectCast(xs.Deserialize(ms), EducatorRegistration)

    End Function

[dmvprof]

This function receives a populated class, and a destination path. If the class is serializable, it doesn't care what kind it is. It converts the class to xml and saves it to the path you specify in the parm.

    Public Shared Function SaveXMLObjectToFile(ByVal IncomingXMLObject As Object, ByVal Path As String) As Boolean

        Dim xmlString As String
        Dim WriteAFile As StreamWriter
        Dim filelocation As String

        Dim MemStream As New System.IO.MemoryStream
        Dim Ser As System.Xml.Serialization.XmlSerializer
        Dim encodingvalue As System.Text.Encoding = System.Text.UTF8Encoding.UTF8
        Dim writer As New System.Xml.XmlTextWriter(MemStream, encodingvalue)

        Dim Result As Boolean

        Try
            File.Delete(Path)
            Ser = New System.Xml.Serialization.XmlSerializer(IncomingXMLObject.GetType)
            Ser.Serialize(writer, IncomingXMLObject)
            MemStream = writer.BaseStream 'as system.io.memorystream
            xmlString = UTF8ByteArrayToString(MemStream.ToArray())   'Will Not Convert Byte Array from Diagram
            filelocation = Path
            WriteAFile = TheFileIn.AppendText(filelocation)
            WriteAFile.Write(xmlString)
            WriteAFile.Close()
            Result = True
        Catch e As Exception
            Result = False
        End Try

        Return Result

    End Function

[kumika]

Thanks guys. I will try this as soon as I get to my desk. If I don't come back, it would have worked. Thanks a lot.

[wild_bill]

Please come back and mark the thread resolved using thread tools if the suggestions worked.

[kumika]

Yes the function draws data from a populated class, Xmlserialize and save it. What still puzzles me though is do I pass just one object to the function or do I need to create and pass object for each of the five records classes? IF I pass one object, for which class? Like I said when I pass object for EducatorRegistration Class I get empty file. At last I had to process one record class at a time. Is this the best wAy to do it? I have also learnt that I needed to use DOM technology to build the XML document. My first time to learn and use this. Thanks a lot guys I have learnt at lot in the past few weeks,

[wild_bill]

Using the class I provided, this works for me. I rewrote dmvprof's serialize method.

    Sub Main()

        'get data from file
        Dim xmlData = IO.File.ReadAllText("C:\temp1\EducatorRegistration.xml")
        'create object from data
        Dim o = DeserializeFromString(xmlData)

        'save object to XML File
        SaveXMLObjectToFile(o, "C:\temp1\EducatorRegistration(2).xml")
    End Sub

    Private Function DeserializeFromString(ByVal input As String) As EducatorRegistration

        'Convert to byte array
        Dim encoding As New System.Text.UnicodeEncoding
        Dim bytes() As Byte = encoding.GetBytes(input)

        'read bytes into stream
        Dim ms As New System.IO.MemoryStream
        ms.Write(bytes, 0, bytes.Length)
        ms.Position = 0

        'get object from bytes
        Dim xs As New Xml.Serialization.XmlSerializer(GetType(EducatorRegistration))
        Return DirectCast(xs.Deserialize(ms), EducatorRegistration)

    End Function

    Public Sub SaveXMLObjectToFile(ByVal IncomingXMLObject As Object, ByVal Path As String)

        'Serialize object to a text file.
        Dim objStreamWriter As New IO.StreamWriter(Path)
        Dim x As New XmlSerializer(IncomingXMLObject.GetType)
        x.Serialize(objStreamWriter, IncomingXMLObject)
        objStreamWriter.Close()

    End Sub

[dmvprof]

I'm not sure I understand your question entirely. It sounds to me like haven't populated the Class properly prior to serializing it.

I have a "UserToken" that I pass around in one of my apps. It has it's local fields as well as an array of the separate class "MenuOptions"

Here is the definition for each of these classes.

Public Class UserToken

    Public UserName As String
    Public Supervisor As Boolean
    Public Division As String
    Public PersonID As Integer
    Public FullName As String
    Public MenuOptions As MenuOption()

End Class

Public Class MenuOption

    Public MenuCategory As String
    Public MenuOptionText As String
    Public OptionToExecute As String
    Public OnlineOnly As Boolean
    Public OptionEnabled As Boolean

End Class

To populate this class, I use the following method. (abbreviated)

        If dr.HasRows Then
                    dr.Read()
                       With NewToken
                            .Division = dr("Division").ToString()
                            .Supervisor = dr("Supervisor")
                            .UserName = parmUserId
                            .PersonID = dr("PersonID")
                            .FullName = dr("FullName")
                         End With

                         dr.Close()

                         NewToken.MenuOptions = AuthorizeUser(parmUserId)

                  End If

My array of MenuOptions has to be populated elsewhere. I have to create a New instance of it, populate it, and then set the Array of MenuOptions defined in my UserToken Class equal to the one I just created.

I do this above with the line

NewToken.MenuOptions = AuthorizeUser(parmUserId)

    Private Function AuthorizeUser(ByRef UserName As String) As MenuOption()

        Dim MenuOptions As List(Of MenuOption)

        sb.Append("SELECT c.[CategoryName], o.[OptionText], o.[OptionToExecute], o.[OnlineOnly], o.[OptionEnabled] ")
        sb.Append(" FROM [VAPDLIB].[Police].[menuUserGroups] g,")
        
        <SNIP>

        DR = sqlCommand.ExecuteReader

        Do While (DR.Read())
            MenuOptions.Add(GetMenuOption(DR))
        Loop

        DR.Close()


        Return MenuOptions.ToArray()

    End Function

    Private Function GetMenuOption(ByVal dr As SqlDataReader) As MenuOption

        Dim NewOption As New MenuOption

        With NewOption
            .MenuCategory = dr("CategoryName").ToString()
            .MenuOptionText = dr("OptionText").ToString()
            .OptionToExecute = dr("OptionToExecute").ToString()
            .OnlineOnly = dr("OnlineOnly")
            .OptionEnabled = dr("OptionEnabled")
        End With

        Return NewOption

    End Function

Once you have your class populated properly, serializing it is a breeze.

To serialize both the "UserToken" and it's "MenuOptions", I just use the "UserToken" object that contains the "MenuOptions".

[techgnome]

It sounds to me like haven't populated the Class properly prior to serializing it.

That's what I thought too...

-tg

[kumika]

I know I have taken a bit longer to finalize this thread. Its because I needed to do some background reading in order to master what is going on here. I want to thank you especially dmvprof and techgnome for their help. Dmvprof gave me a breakthrough although it took me some addiitional reading to grasp his solution. Thanks a lot. Problem solved!