Saving Multiple Objects / Classes in one XML file

I've been away for programming for a while and it took me a bit to get used to XML serialization. My first issue was with multiple classes of different types into one file. I has to combine a couple answers together to get the hang of it, though it makes perfect sense now. I thought I would post this for anyone else who might want an example to help understand.

For those who don't a lot of XML experience, proper XML has one root object. This object can be a List(of ...), so if you need to save multiple instances of a single data type or class you can use below...

Code:

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Public Sub SaveMany()
        Dim TheList as New List(Of String)
        TheList.Add("Apple")
        TheList.Add("Banana")
        Dim mydocpath As String =
            Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments)
        Dim writer As New System.Xml.Serialization.XmlSerializer(GetType(List(Of String))
        Dim file As New System.IO.StreamWriter(mydocpath + "\Test.xml")
        writer.Serialize(file, TheList)
        file.Close()
End Sub

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If you have different data type or classes you will need to create a class that contains them. In the below I create a card class and pet class, put them in lists to save multiple of each them combine those in a single super class that can be output in one XML.

Code:

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Public Class clsCard
    Private myRank As String
    Private mySuit As String

    Property Rank() As String
        Get
            Return myRank
        End Get
        Set(value As String)
            myRank = value
        End Set
    End Property
    Property Suit() As String
        Get
            Return mySuit
        End Get
        Set(value As String)
            mySuit = value
        End Set
    End Property
End Class

Public Class clsPet
    Private myPetName As String
    Private myPetType As String
    Private myAge As Int16

    Property PetName() As String
        Get
            Return myPetName
        End Get
        Set(value As String)
            myPetName = value
        End Set
    End Property
    Property PetType() As String
        Get
            Return myPetType
        End Get
        Set(value As String)
            myPetType = value
        End Set
    End Property
    Property Age As Int32
        Get
            Return myAge
        End Get
        Set(value As Int32)
            myAge = value
        End Set
    End Property
End Class

Public Class clsRootForXML
    Private myRecordDate As Date
    Private myCardList As List(Of clsCard)
    Private myPetList As List(Of clsPet)
    Property RecordDate As Date
        Get
            Return myRecordDate
        End Get
        Set(value As Date)
            myRecordDate = value
        End Set
    End Property
    Property CardList As List(Of clsCard)
        Get
            Return myCardList
        End Get
        Set(value As List(Of clsCard))
            myCardList = value
        End Set
    End Property
    Property PetList As List(Of clsPet)
        Get
            Return myPetList
        End Get
        Set(value As List(Of clsPet))
            myPetList = value
        End Set
    End Property
End Class

Public Sub CreateOneXML()

        Dim card1 As New clsCard
        Dim card2 As New clsCard
        Dim card3 As New clsCard
        Dim theseCards As New List(Of clsCard)
        card1.Rank = "Ace"
        card1.Suit = "Spades"
        card2.Rank = "King"
        card2.Suit = "Hearts"
        card3.Rank = "10"
        card3.Suit = "Diamonds"
        theseCards.Add(card1)
        theseCards.Add(card2)
        theseCards.Add(card3)

        Dim pet1 As New clsPet
        Dim pet2 As New clsPet
        Dim thesePets As New List(Of clsPet)
        pet1.PetName = "Spot"
        pet1.PetType = "Dog"
        pet1.Age = 3
        pet2.PetName = "Whiskers"
        pet2.PetType = "Cat"
        pet2.Age = 7
        thesePets.Add(pet1)
        thesePets.Add(pet2)

        Dim oneRootObject As New clsRootForXML
        oneRootObject.RecordDate = #01/01/2001#
        oneRootObject.CardList = theseCards
        oneRootObject.PetList = thesePets

        Dim mydocpath As String =
            Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments)
        Dim writer As New System.Xml.Serialization.XmlSerializer(GetType(clsRootForXML))
        Dim file As New System.IO.StreamWriter(mydocpath + "\Test.xml")
        writer.Serialize(file, oneRootObject)
        file.Close()
    End Sub

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the resulting xml is

Code:

---

<?xml version="1.0" encoding="utf-8"?>
<clsRootForXML xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <RecordDate>2001-01-01T00:00:00</RecordDate>
  <CardList>
    <clsCard>
      <Rank>Ace</Rank>
      <Suit>Spades</Suit>
    </clsCard>
    <clsCard>
      <Rank>King</Rank>
      <Suit>Hearts</Suit>
    </clsCard>
    <clsCard>
      <Rank>10</Rank>
      <Suit>Diamonds</Suit>
    </clsCard>
  </CardList>
  <PetList>
    <clsPet>
      <PetName>Spot</PetName>
      <PetType>Dog</PetType>
      <Age>3</Age>
    </clsPet>
    <clsPet>
      <PetName>Whiskers</PetName>
      <PetType>Cat</PetType>
      <Age>7</Age>
    </clsPet>
  </PetList>
</clsRootForXML>

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Hope this helps.

Thread moved to CodeBank, as it is a working snippet/example rather than a question.