Long Post, thanks for your patience...
I have and XML file that looks something like this:
<?xml version="1.0" encoding="utf-8" ?>
<Settings>
<Location>
<X>30</X>
<Y>40</Y>
</Location>
<Size>
<Width>140</Width>
<Height>56</Height>
</Size>
<WindowState>Maximized</WindowState>
<SplitPosition>335</SplitPosition>
<ShowStatusBar>true</ShowStatusBar>
<Connections>
<Connection>
<Database>MyFirstDatabase</Database>
<DataSource>MyServer</DataSource>
<IntegratedSecurity>true</IntegratedSecurity>
<ConnectionName>MyFirstConnection</ConnectionName>
</Connection>
<Connection>
<Database>MySecondDatabase</Database>
<DataSource>MyServer</DataSource>
<Password>mypassword</Password>
<UserName>mylogin</UserName>
<ConnectionName>MySecondConnection</ConnectionName>
</Connection>
<Connection>
<Database>C:\Reports.mdb</Database>
<DataSource>C:\Reports.mdb</DataSource>
<Provider>Access</Provider>
<ConnectionName>LOCALACCESS_C:\REPORTS.MDB</ConnectionName>
</Connection>
</Connections>
</Settings>
(Actually it looks exactly like that. :-) )
I have a class Settings, optConnection, optConnectionCollection (Code Below).
When I call the subroutine to open the XML file (In the Settings Class) and thus Deserialize into the objects, my connectioncollection does not contain any connections. What have I missed here?
--------------------------------
Option Explicit On
Option Strict On
Imports System.IO
Imports System.Xml.Serialization
Imports System.Drawing
Imports System.Windows.Forms
Public Class Settings
Private m_ptLocation As Point = Point.Empty
Private m_sizeSize As Size = Size.Empty
Private m_fwsWindowState As FormWindowState
Private m_iSplitPosition As Integer
Private m_bShowStatusBar As Boolean
Private m_Connections As optConnectionCollection
' Some variables we need to start processing
Private Shared m_strXMLFileName As String = ""
Private Shared m_oSerializer As XmlSerializer = Nothing
Public Sub New()
End Sub
' Open = Deserialize the XML file to the Objects
Public Shared Function Open(ByVal XMLFileName As String) As Settings
Dim oOverrides As XmlAttributeOverrides = New XmlAttributeOverrides
Dim oAttributes As XmlAttributes
Dim sAttr As XmlElementAttribute
If (XMLFileName.Length > 0) Then
m_strXMLFileName = XMLFileName
Else
Throw New ArgumentException("Empty filename is not legal." & Environment.NewLine & "Parameter name: XMLFileName", "XMLFileName")
End If
' --- I'VE TRIED THIS BUT COMMENTED IT OUT, DOESN'T SEEM TO MATTER ----
'sAttr = New XmlElementAttribute("Connections")
'sAttr.Type = GetType(optConnectionCollection)
'oAttributes = New XmlAttributes
'oAttributes.XmlElements.Add(sAttr)
'oOverrides.Add(GetType(Settings), "Connections", oAttributes)
' Create the XmlSerializer using the XmlAttributeOverrides.
Try
m_oSerializer = New XmlSerializer(GetType(Settings), oOverrides)
Dim fs As New FileStream(m_strXMLFileName, FileMode.Open)
Return CType(m_oSerializer.Deserialize(fs), Settings)
Catch ex As Exception
MsgBox(ex.Message)
End Try
End Function
' Close = Serialize the Objects to the XML File
Public Sub Close(Optional ByVal XMLFileName As String = "")
Dim oWriter As StreamWriter
If (XMLFileName.Length > 0) Then
m_strXMLFileName = XMLFileName
End If
If (m_strXMLFileName.Length = 0) Then
' No filename given; cannot save
Else
oWriter = New StreamWriter(m_strXMLFileName)
m_oSerializer.Serialize(oWriter, Me)
oWriter.Close()
End If
End Sub
Public Property Connections() As optConnectionCollection
Get
Return m_Connections
End Get
Set(ByVal Value As optConnectionCollection)
m_Connections = Value
End Set
End Property
Public ReadOnly Property XMLFileName() As String
Get
Return m_strXMLFileName
End Get
End Property
Public Property Location() As Point
Get
Return m_ptLocation
End Get
Set(ByVal Value As Point)
m_ptLocation = Value
End Set
End Property
Public Property Size() As Size
Get
Return m_sizeSize
End Get
Set(ByVal Value As Size)
m_sizeSize = Value
End Set
End Property
Public Property ShowStatusBar() As Boolean
Get
Return m_bShowStatusBar
End Get
Set(ByVal Value As Boolean)
m_bShowStatusBar = Value
End Set
End Property
Public Property WindowState() As FormWindowState
Get
Return m_fwsWindowState
End Get
Set(ByVal Value As FormWindowState)
m_fwsWindowState = Value
End Set
End Property
Public Property SplitPosition() As Integer
Get
Return m_iSplitPosition
End Get
Set(ByVal Value As Integer)
m_iSplitPosition = Value
End Set
End Property
End Class
'<FILE clsConnection.vb>
Option Explicit On
Option Strict On
Public Class optConnection
Implements IDbConnection
Public Enum eProvider
SQLServer = 0
Access = 1
FileDSN = 2
SystemDSN = 3
UserDSN = 4
End Enum
Private Const ACCESS_PROVIDER As String = "Microsoft.Jet.OLEDB.4.0"
Private m_szConnectionString As String
Private m_iConnectionTimeout As Integer
Private m_szDataSource As String
Private m_szDatabase As String
Private m_bIntegratedSecurity As Boolean
Private m_szPassword As String
Private m_iProvider As eProvider = eProvider.SQLServer
Private m_szServerVersion As String
Private m_szUserName As String
Private m_ConnectionName As String
Public Sub New()
MyBase.New()
End Sub
Public Overridable Property ConnectionName() As String
Get
Return m_ConnectionName
End Get
Set(ByVal Value As String)
m_ConnectionName = Value
End Set
End Property
Public Overridable Property DataSource() As String
Get
Return m_szDataSource
End Get
Set(ByVal szDataSource As String)
If (State <> ConnectionState.Closed) Then
Throw New InvalidOperationException("The 'DataSource' property may only be changed while the connection is closed. The current state of the connection is " & State.ToString() & ".")
End If
If (szDataSource Is Nothing) Then
m_szDataSource = ""
Else
m_szDataSource = szDataSource
End If
End Set
End Property
Public Overridable Property IntegratedSecurity() As Boolean
Get
Return m_bIntegratedSecurity
End Get
Set(ByVal bIntegratedSecurity As Boolean)
If (State <> ConnectionState.Closed) Then
Throw New InvalidOperationException("The 'IntegratedSecurity' property may only be changed while the connection is closed. The current state of the connection is " & State.ToString() & ".")
End If
m_bIntegratedSecurity = bIntegratedSecurity
End Set
End Property
Public Overridable Property Password() As String
Get
Return m_szPassword
End Get
Set(ByVal szPassword As String)
If (State <> ConnectionState.Closed) Then
Throw New InvalidOperationException("The 'Password' property may only be changed while the connection is closed. The current state of the connection is " & State.ToString() & ".")
End If
If (szPassword Is Nothing) Then
m_szPassword = ""
Else
m_szPassword = szPassword
End If
End Set
End Property
Public Property Provider() As eProvider
Get
Return m_iProvider
End Get
Set(ByVal iProvider As eProvider)
If (State <> ConnectionState.Closed) Then
Throw New InvalidOperationException("The 'Provider' property may only be changed while the connection is closed. The current state of the connection is " & State.ToString() & ".")
End If
m_iProvider = iProvider
End Set
End Property
Public Overridable Property ServerVersion() As String
Get
Return m_szServerVersion
End Get
Set(ByVal Value As String)
m_szServerVersion = Value
End Set
End Property
Public Overridable Property UserName() As String
Get
Return m_szUserName
End Get
Set(ByVal szUserName As String)
If (szUserName Is Nothing) Then
m_szUserName = ""
Else
m_szUserName = szUserName
End If
End Set
End Property
Public Overloads Function BeginTransaction() As System.Data.IDbTransaction Implements System.Data.IDbConnection.BeginTransaction
End Function
Public Overloads Function BeginTransaction1(ByVal il As System.Data.IsolationLevel) As System.Data.IDbTransaction Implements System.Data.IDbConnection.BeginTransaction
End Function
Public Sub ChangeDatabase(ByVal databaseName As String) Implements System.Data.IDbConnection.ChangeDatabase
End Sub
Public Sub Close() Implements System.Data.IDbConnection.Close
End Sub
Public ReadOnly Property ConnectionTimeout() As Integer Implements System.Data.IDbConnection.ConnectionTimeout
Get
End Get
End Property
Public Function CreateCommand() As System.Data.IDbCommand Implements System.Data.IDbConnection.CreateCommand
End Function
Public Sub Open() Implements System.Data.IDbConnection.Open
End Sub
Public ReadOnly Property State() As System.Data.ConnectionState Implements System.Data.IDbConnection.State
Get
End Get
End Property
Public Overridable Property ConnectionString() As String Implements System.Data.IDbConnection.ConnectionString
Get
Return m_szConnectionString
End Get
Set(ByVal szConnectionString As String)
If (State <> ConnectionState.Closed) Then
Throw New InvalidOperationException("The 'ConnectionString' property may only be changed while the connection is closed. The current state of the connection is " & State.ToString() & ".")
End If
If (szConnectionString Is Nothing) Then
m_szConnectionString = ""
Else
m_szConnectionString = szConnectionString
End If
End Set
End Property
Public Overridable ReadOnly Property Database() As String Implements System.Data.IDbConnection.Database
Get
Return m_szDatabase
End Get
End Property
Public Sub Dispose() Implements System.IDisposable.Dispose
End Sub
End Class
'<FILE clsConnectionCollection.vb >
Option Explicit On
Option Strict On
Public Class optConnectionCollection
Inherits CollectionBase
Public Sub New()
MyBase.New()
End Sub
Public Sub New(ByVal oConnections As ICollection)
MyBase.New()
AddRange(oConnections)
End Sub
Default Public Overloads Property Item(ByVal iIndex As Integer) As optConnection
Get
Return CType(List.Item(iIndex), optConnection)
End Get
Set(ByVal Value As optConnection)
Add(Value)
End Set
End Property
Public Function Add(ByVal oConnection As optConnection) As Integer
Return List.Add(oConnection)
End Function
Public Sub AddRange(ByVal oConnections As ICollection)
Dim oEntry As DictionaryEntry
Dim oValue As Object
If (TypeOf oConnections Is IDictionary) Then
For Each oEntry In CType(oConnections, IDictionary)
List.Add(oEntry.Value)
Next oEntry
Else
For Each oValue In oConnections
List.Add(oValue)
Next oValue
End If
End Sub
Public Overloads Sub Remove(ByVal szName As String)
Dim i As Integer
Dim oConnection As optConnection
For i = 0 To List.Count - 1
oConnection = CType(List(i), optConnection)
If (oConnection.ConnectionName = szName) Then
List.RemoveAt(i)
Return
End If
Next i
' Connection was not found in the collection
' TODO: Throw an appropriate exception
Throw New Exception
End Sub
Public Overloads Sub Remove(ByVal oConnection As optConnection)
List.Remove(oConnection)
End Sub
End Class
<FILE - Form1.vb - Simple form to open/close the file>
Imports Settings_Class
Public Class Form1
Inherits System.Windows.Forms.Form
Private m_Settings As Settings
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
m_Settings = m_Settings.Open("XMLFIlE3.xml")
End Sub
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
m_Settings.Close("XMLFilE4.xml")
m_Settings = Nothing
End Sub
End Class
Thanks for any help.
From: John Manion
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Posted by a user from .NET 247 (http://www.dotnet247.com/)
<Id>i0oFZ6jppEOcTC58KQwXlA==</Id>
