Hi folks,
I am buidling this app where I use deserialization to obtain a List of the object "Contact", so far so good. When I try to retrieve the first element from this obtained list (which I sorted and declared in "objsortedData" I get this InvalidCastException:
{System.InvalidCastException: Unable to cast object of type 'Contact' to type 'System.Collections.IEnumerable'. at AdresboekApp.MainPage..ctor()}
See my code below, is it necessary to cast to IEnumerable? And if so, how do I correctly cast my list(values) so that I can use indexation to declare the "firstPerson" variable?
Main Sub:
Function GeneratePersonData wich generates a default list of Contact
Class Contact:
I am buidling this app where I use deserialization to obtain a List of the object "Contact", so far so good. When I try to retrieve the first element from this obtained list (which I sorted and declared in "objsortedData" I get this InvalidCastException:
{System.InvalidCastException: Unable to cast object of type 'Contact' to type 'System.Collections.IEnumerable'. at AdresboekApp.MainPage..ctor()}
See my code below, is it necessary to cast to IEnumerable? And if so, how do I correctly cast my list(values) so that I can use indexation to declare the "firstPerson" variable?
Main Sub:
Code:
Public Sub New()
InitializeComponent()
SupportedOrientations = SupportedPageOrientation.Portrait Or SupportedPageOrientation.Landscape
'Save default persondata to Contacten.xml file on local device
Dim xmlWriterSettings As XmlWriterSettings = New XmlWriterSettings()
xmlWriterSettings.Indent = True
Dim local As System.IO.IsolatedStorage.IsolatedStorageFile = System.IO.IsolatedStorage.IsolatedStorageFile.GetUserStoreForApplication()
If Not local.DirectoryExists("\Assets") Then local.CreateDirectory("\Assets")
Using stream As IsolatedStorageFileStream = local.OpenFile("\Assets\Contacten.xml", FileMode.Create)
Dim serializer As XmlSerializer = New XmlSerializer(GetType(List(Of Contact)))
Using xmlWriter As XmlWriter = xmlWriter.Create(stream, xmlWriterSettings)
serializer.Serialize(xmlWriter, GeneratePersonData())
End Using
End Using
'Show first contact in Contacten.xml file on local device
Using stream As IsolatedStorageFileStream = local.OpenFile("\Assets\Contacten.xml", FileMode.Open)
Dim serializer As XmlSerializer = New XmlSerializer(GetType(List(Of Contact)))
Dim persondata As List(Of Contact) = CType(serializer.Deserialize(stream), List(Of Contact))
Dim objsortedData = persondata.OrderBy(Function(t) CStr(t.Firstname))
Dim firstPerson = objsortedData(0)
Me.listBox.ItemsSource = firstPerson
End Using
End SubCode:
'Generate default persondata
Private Function GeneratePersonData() As List(Of Contact)
Dim persondata As List(Of Contact) = New List(Of Contact)()
persondata.Add(New Contact() With {
.Firstname = "Louis",
.Lastname = "van Gaal",
.Emailadress = "louisvangaal@prive.nl"
})
persondata.Add(New Contact() With {
.Firstname = "Patrick",
.Lastname = "Kluivert",
.Emailadress = "patrickkluivert@prive.nl"
})
persondata.Add(New Contact() With {
.Firstname = "Robin",
.Lastname = "van Persie",
.Emailadress = "robinvanpersie@prive.nl"
})
persondata.Add(New Contact() With {
.Firstname = "Arjen",
.Lastname = "Robben",
.Emailadress = "arjenrobben@prive.nl"
})
Return persondata
End FunctionCode:
' Storage of class Contact data
Private _firstname As String
Private _lastname As String
Private _email As String
Public Property Firstname() As String
Get
Return _firstname
End Get
Set(ByVal value As String)
_firstname = value
End Set
End Property
Public Property Lastname() As String
Get
Return _lastname
End Get
Set(ByVal value As String)
_lastname = value
End Set
End Property
Public Property Emailadress() As String
Get
Return _email
End Get
Set(ByVal value As String)
_email = value
End Set
End Property
End Class
End Class