The task is to import every file that is dropped into a specific folder on my local drive into NAV. The solution is a windows service programmed in Visual Studio 2008 VB.NET.
The first step is to create a web service in Dynamics NAV that accepts a text line and a file name. Another function to remove the file if the import fails and the third to process the file after it has been imported.
The vb.net code from Visual Studio
[code lang=”vb”]Imports System
Imports System.Timers
Imports System.Net
Imports System.IO
Public Class FileImportService
Dim Salvor1 As Salvor.SalvorWebService
Dim Timer1 As System.Timers.Timer
Dim User As New System.Net.NetworkCredential
Protected Overrides Sub OnStart(ByVal args() As String)
‘ Add code here to start your service. This method should set things
‘ in motion so your service can do its work.
Salvor1 = New Salvor.SalvorWebService
User.Domain = "<Domain>"
User.UserName = "<User>"
User.Password = "<Password>"
Salvor1.Credentials = User
Timer1 = New System.Timers.Timer(30000)
AddHandler Timer1.Elapsed, AddressOf OnTimedEvent
Timer1.Interval = 30000
Timer1.Enabled = True
Timer1.Start()
WriteDebug("Timer 1 Started")
‘ If the timer is declared in a long-running method, use
‘ KeepAlive to prevent garbage collection from occurring
‘ before the method ends.
GC.KeepAlive(Timer1)
End Sub
Protected Overrides Sub OnStop()
‘ Add code here to perform any tear-down necessary to stop your service.
End Sub
Protected Sub OnTimedEvent(ByVal source As Object, ByVal e As ElapsedEventArgs)
Timer1.Enabled = False
Timer1.Stop()
WriteDebug("File Event Started")
Try
If Salvor1.AboutCompany = "SAM" Then
ReadFolder()
End If
Catch ex As Exception
WriteToEventLog("Web Service unavailable:" & ex.ToString, EventLogEntryType.Error)
End Try
Timer1.Enabled = True
Timer1.Start()
End Sub
Protected Sub ReadFolder()
Dim dirInfo As New DirectoryInfo(My.Settings.ImportFolder)
Dim FileArray As FileInfo() = dirInfo.GetFiles()
For Each TextFile In FileArray
If ReadFile(TextFile) Then
WriteDebug("Check File: " & TextFile.Name)
If Salvor1.ProcessFile(TextFile.Name) Then
DeleteFile(TextFile)
Else
WriteDebug("Rollback File: " & TextFile.Name)
Salvor1.RemoveFile(TextFile.Name)
End If
Else
Salvor1.RemoveFile(TextFile.Name)
End If
Next
End Sub
Protected Function ReadFile(ByVal TextFile As FileInfo) As Boolean
Dim Success As Boolean
Try
If File.Exists(TextFile.FullName) Then
Dim ioFile As New StreamReader(TextFile.FullName)
Dim ioLine As String
Success = True
While Not ioFile.EndOfStream
ioLine = ioFile.ReadLine
Success = Success And Salvor1.InsertLine(TextFile.Name, ioLine)
End While
ioFile.Close()
End If
Catch ex As Exception
Success = False
WriteToEventLog("Import of file " & TextFile.FullName & " failed:" & ex.ToString, EventLogEntryType.Error)
End Try
Return Success
End Function
Protected Sub DeleteFile(ByVal TextFile As FileInfo)
Try
WriteDebug("Delete File: " & TextFile.Name)
TextFile.Delete()
Catch ex As Exception
WriteToEventLog("Failed to delete file " & TextFile.FullName & ":" & ex.ToString, EventLogEntryType.Error)
End Try
End Sub
Protected Sub WriteToEventLog(ByVal Message As String, ByVal EntryType As EventLogEntryType)
Dim MyLog As New EventLog()
‘ Check if the the Event Log Exists
If Not Diagnostics.EventLog.SourceExists(Me.ServiceName) Then
Diagnostics.EventLog.CreateEventSource(Me.ServiceName, Me.ServiceName & " Log")
‘ Create Log
End If
MyLog.Source = Me.ServiceName
‘ Write to the Log
Diagnostics.EventLog.WriteEntry(MyLog.Source, Message, EntryType)
End Sub
Protected Sub WriteDebug(ByVal Message As String)
If My.Settings.Debug Then
WriteToEventLog(Message, EventLogEntryType.Information)
End If
End Sub
End Class[/code]
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