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copied!<p>I would create a class that used a .NET DataSet and DataTable to store the ids and messages (and whatever else you need).</p> <p>That way the class can use the DataSet.WriteXML() and DataSet.ReadXML() to save/load from any filename you specify and you don't have to worry about "hand crafting" the XML format yourself.</p> <p>This sounded like a handy class to have, so I wrote one up as a "proof of concept":</p> <pre><code>'************************************************************************* ' Class: MsgFile ' Author: Ron Savage ' Date: 05/14/2009 ' ' This class is an example for using an XML file to hold messages to be ' displayed by an application. ' ' Modification History ' Date Init Comment ' 05/14/2009 RS Created. '************************************************************************* Imports Microsoft.VisualBasic Imports System.IO Public Class MsgFile '************************************************************************* ' Class Variables '************************************************************************* Private MsgFile As String Private msgData As DataSet Private msgTable As DataTable '************************************************************************* ' Sub: New() ' Author: Ron Savage ' Date: 05/14/2009 ' ' Creates a new MsgFile from an existing file, or creates an empty one ' with the specified file name. '************************************************************************* Sub New(ByVal msg_File As String) Dim srcFile As New FileInfo(msg_File) If (srcFile.Exists()) Then msgData = New DataSet() Load(msg_File) Else NewFile(msg_File) End If End Sub '************************************************************************* ' Sub: NewFile() ' Author: Ron Savage ' Date: 05/14/2009 ' ' Creates a new XML message file. '************************************************************************* Sub NewFile(ByVal msg_File As String) Me.MsgFile = msg_File If (IsNothing(msgData)) Then msgData = New DataSet("MyAppMessages") msgTable = New DataTable("Messages") msgTable.Columns.Add(New DataColumn("Id", GetType(System.Int32), Nothing, MappingType.Attribute)) msgTable.Columns.Add(New DataColumn("Text", GetType(System.String), Nothing, MappingType.Attribute)) msgData.Tables.Add(msgTable) setMessage(0, "New file created") End If Save() End Sub '************************************************************************* ' Sub: Load() ' Author: Ron Savage ' Date: 05/14/2009 ' ' Loads an existing XML message file into the dataset. '************************************************************************* Public Sub Load(ByVal msgFileName As String) Dim srcFile As FileInfo = Nothing Me.MsgFile = msgFileName srcFile = New FileInfo(msgFileName) msgData.Clear() If (srcFile.Exists()) Then msgData.ReadXml(msgFileName) msgTable = msgData.Tables("Messages") End If End Sub '************************************************************************* ' Sub: Save() ' Author: Ron Savage ' Date: 10/05/2008 ' ' This routine saves the DataSet to an XML file. '************************************************************************* Public Overridable Sub Save() If (Not IsNothing(msgData) And Not MsgFile.Equals("")) Then Dim fileWriter As StreamWriter = New StreamWriter(MsgFile) msgData.WriteXml(fileWriter) fileWriter.Close() End If End Sub '************************************************************************* ' Sub: getMessage() ' Author: Ron Savage ' Date: 05/14/2009 ' ' This gets the text of the message. '************************************************************************* Public Function getMessage(ByVal msgId As String) As String Dim rowsFound() As System.Data.DataRow Dim msgText As String = "" If (Not IsNothing(msgTable)) Then rowsFound = msgTable.Select("Id = " + msgId.ToString) If (rowsFound.Length > 0) Then msgText = rowsFound(0).Item("Text").ToString End If End If Return (msgText) End Function '************************************************************************* ' Sub: setMessage() ' Author: Ron Savage ' Date: 05/14/2009 ' ' This sets the text of the message. '************************************************************************* Public Sub setMessage(ByVal msgId As Integer, ByVal msgText As String) Dim rowsFound() As System.Data.DataRow Dim msgRow As System.Data.DataRow If (Not IsNothing(msgTable)) Then rowsFound = msgTable.Select("Id = " + msgId.ToString) If (rowsFound.Length > 0) Then msgRow = rowsFound(0) msgRow.Item("Id") = msgId msgRow.Item("Text") = msgText Else msgRow = msgTable.NewRow() msgRow.Item("Id") = msgId msgRow.Item("Text") = msgText msgTable.Rows.Add(msgRow) End If End If Save() End Sub End Class </code></pre>

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