Managing Dialup connection
2.84/5 (17 votes)
Mange your Internet connection .
Introduction
I am going to tell you in this artical about how you can access your PC from outside, using simple mobile Internet connection which is frequently disconnected. Normally our mobile GPRS connection gets Dynamic IP(which is frequently changed).
Now i want connect to my FTP floder located at my home PC. So that i created a application, this application automatically connected to the dial-up connection if it's disconnected, and send a mail to your mail id with the IP address.
Background
I taken some code from the code project for the network quality check.
I used "rasdial.exe" for the dial a dial up connection. located at ("c:\windows\system32\rasdial.exe")
Using the code
Before using this code user have set some modification in their connections, code.
ISP Entry Name: Please take care about the ISP entry name, This name don't put spaces and other special characters.
And also remove the redial option for the dialup connection properties....
SMTP mail : Change the mail address/password in the code. for sender mail ID. this mail id must be enable with the POP3,SMTP Out .
#Region "Imports"
Imports System
Imports System.IO
Imports System.Net
Imports System.Net.Mail
#End Region
Public Class Manage
#Region "Declarations"
''' <summary>
''' Process Delaration , used for the run external command (rasdial.exe)
''' </summary>
Public MyProcess As New System.Diagnostics.Process
''' <summary>
''' Holds the Current IP address
''' </summary>
Public PresentIPAddress As String = ""
''' <summary>
''' Quality of the connection (String Type)
''' </summary>
Public Conn_Qulity As String = "Bad"
''' <summary>
''' windows API function for Internet Connection type and connection quality.
''' </summary>
Private Declare Function InternetGetConnectedState Lib _
"wininet.dll" (ByRef lpSFlags As Int32, _
ByVal dwReserved As Int32) As Boolean
''' <summary>
''' enum used for the internet connection type.
''' </summary>
Public Enum InetConnState
modem = &H1
lan = &H2
proxy = &H4
ras = &H10
offline = &H20
configured = &H40
End Enum
#End Region
#Region "Network Handlers/Methods"
''' <summary>
''' Network Connection Handler.
''' </summary>
Private Sub Handle_NetworkAvailabilityChanged()
AddHandler My.Computer.Network.NetworkAvailabilityChanged, _
AddressOf MyComputerNetwork_NetworkAvailabilityChanged
DisplayAvailability(My.Computer.Network.IsAvailable)
End Sub
''' <summary>
''' Network Availability changing Handler,
''' </summary>
''' <remarks>
''' *** Problems witn when two network connctions are present.
''' </remarks>
Private Sub MyComputerNetwork_NetworkAvailabilityChanged( _
ByVal sender As Object, _
ByVal e As Devices.NetworkAvailableEventArgs)
DisplayAvailability(e.IsNetworkAvailable)
End Sub
''' <summary>
''' Display availability methods
''' </summary>
''' <param name="available">
''' True/False
''' </param>
Private Sub DisplayAvailability(ByVal available As Boolean)
Application.DoEvents()
If available = True Then
'' Verifiying for Genuine Connection
Try
Application.DoEvents()
MyProcess.StartInfo.FileName = "c:\myip.bat"
MyProcess.StartInfo.Arguments = ""
MyProcess.StartInfo.UseShellExecute = False
MyProcess.StartInfo.WindowStyle = ProcessWindowStyle.Normal
'Process.GetCurrentProcess()
Application.DoEvents()
MyProcess.Start()
MyProcess.WaitForExit()
MyProcess.Close()
'System.Diagnostics.Process.Start("c:\myip.bat", "")
Application.DoEvents()
Delay(5000)
Dim line As String = ""
Using sr As StreamReader = New StreamReader("c:\MYIP.txt")
line = sr.ReadToEnd()
End Using
If InStr(UCase(line), UCase(txtISPEntry.Text)) <= 0 Then
lblstatus.Text = "Connecting..."
AppendStatus("Connecting...")
lblstatus.Refresh()
Delay(5000)
Application.DoEvents()
Call DisplayAvailability(False)
End If
Catch ex As Exception
MsgBox(ex.Message)
End Try
lblstatus.Text = "Reading IP Address(s)."
AppendStatus("Reading IP Address(s).")
Dim hostName As String = System.Net.Dns.GetHostName()
Delay(2000)
lblstatus.Text = System.Net.Dns.GetHostByName(hostName).AddressList(0).ToString()
AppendStatus("IP Address : " & System.Net.Dns.GetHostByName(hostName).AddressList(0).ToString())
PresentIPAddress = System.Net.Dns.GetHostByName(hostName).AddressList(0).ToString()
Beep()
Beep()
Beep()
lblstatus.Text = "Connected."
AppendStatus("Connected.")
lblstatus.Refresh()
Check_Net_Conn_Type()
Call Send_email()
Else
lblstatus.Text = "Disconnected."
AppendStatus("Disconnected.")
lblstatus.Refresh()
lblstatus.Text = "Waiting For Connection..."
AppendStatus("Waiting For Connection...")
lblstatus.Refresh()
Application.DoEvents()
lblstatus.Text = "Connecting..."
AppendStatus("Connecting...")
lblstatus.Refresh()
Try
MyProcess.StartInfo.FileName = "rasdial.exe"
If Trim(txtusername.Text) = "" Or Trim(txtpassword.Text) = "" Then
MyProcess.StartInfo.Arguments = txtISPEntry.Text
Else
MyProcess.StartInfo.Arguments = txtISPEntry.Text & " " & txtusername.Text & " " & txtpassword.Text
End If
MyProcess.StartInfo.UseShellExecute = False
MyProcess.StartInfo.WindowStyle = ProcessWindowStyle.Normal
'Process.GetCurrentProcess()
MyProcess.Start()
MyProcess.WaitForExit()
MyProcess.Close()
'System.Diagnostics.Process.Start("rasdial.exe", TextBox5.Text)
Catch ex As Exception
MsgBox(ex.Message)
End Try
Try
Application.DoEvents()
MyProcess.StartInfo.FileName = "c:\myip.bat"
MyProcess.StartInfo.Arguments = ""
MyProcess.StartInfo.UseShellExecute = False
MyProcess.StartInfo.WindowStyle = ProcessWindowStyle.Normal
'Process.GetCurrentProcess()
Application.DoEvents()
MyProcess.Start()
MyProcess.WaitForExit()
MyProcess.Close()
'System.Diagnostics.Process.Start("c:\myip.bat", "")
Application.DoEvents()
Delay(5000)
Dim line As String = ""
Using sr As StreamReader = New StreamReader("c:\MYIP.txt")
line = sr.ReadToEnd()
End Using
If InStr(UCase(line), UCase(txtISPEntry.Text)) <= 0 Then
lblstatus.Text = "Re-Connecting..."
AppendStatus("Re-Connecting...")
lblstatus.Refresh()
Delay(5000)
Application.DoEvents()
Call DisplayAvailability(False)
End If
Catch ex As Exception
MsgBox(ex.Message)
End Try
Beep()
Beep()
Beep()
Application.DoEvents()
End If
End Sub
''' <summary>
''' Force disconnect/re-connect by the User.
''' </summary>
Public Sub Re_Connect()
Try
MyProcess.StartInfo.FileName = "rasdial"
MyProcess.StartInfo.Arguments = txtISPEntry.Text & " /disconnect"
MyProcess.StartInfo.UseShellExecute = False
MyProcess.StartInfo.WindowStyle = ProcessWindowStyle.Normal
'Process.GetCurrentProcess()
MyProcess.Start()
MyProcess.WaitForExit()
MyProcess.Close()
Delay(5000)
Call DisplayAvailability(False)
Catch ex As Exception
MsgBox(ex.Message)
End Try
End Sub
''' <summary>
''' Creats bat file for every fresh run of the application.
''' </summary>
Public Sub Create_MYIP_Batfile()
Dim sr As New FileStream("c:\myip.bat", FileMode.Create)
Dim wr As New StreamWriter(sr)
wr.WriteLine("rasdial >c:\myip.txt")
wr.Close()
sr.Close()
End Sub
''' <summary>
''' Chaking for Network connction type.
''' </summary>
Function Check_Net_Conn_Type() As Boolean
Dim NetFlags As Long
If InternetGetConnectedState(NetFlags, 0) Then
' True
If NetFlags And InetConnState.lan Then
lblconntype.Text = "LAN."
ElseIf NetFlags And InetConnState.modem Then
lblconntype.Text = "Modem."
ElseIf NetFlags And InetConnState.configured Then
lblconntype.Text = "Configured."
ElseIf NetFlags And InetConnState.proxy Then
lblconntype.Text = "Proxy."
ElseIf NetFlags And InetConnState.ras Then
lblconntype.Text = "RAS."
ElseIf NetFlags And InetConnState.offline Then
lblconntype.Text = "Offline."
End If
Else
lblconntype.Text = "Off"
End If
Call CheckInetConnection()
End Function
''' <summary>
''' Checking for Neteork connction quality.
''' </summary>
Function CheckInetConnection() As Boolean
Dim lngFlags As Long
If InternetGetConnectedState(lngFlags, 0) Then
' True
If lngFlags And InetConnState.lan Then
Select Case Conn_Qulity
Case "Good"
lblqlty.Text = " Good"
Conn_Qulity = "Good"
Case "Intermittent"
lblqlty.Text = " Good"
Conn_Qulity = "Good"
Case "Bad"
lblqlty.Text = " Intermittent"
Conn_Qulity = "Intermittent"
End Select
Me.Refresh()
ElseIf lngFlags And InetConnState.modem Then
Select Case Conn_Qulity
Case "Good"
lblqlty.Text = " Good"
Conn_Qulity = "Good"
Case "Intermittent"
lblqlty.Text = " Good"
Conn_Qulity = "Good"
Case "Bad"
lblqlty.Text = " Intermittent"
Conn_Qulity = "Intermittent"
End Select
ElseIf lngFlags And InetConnState.configured Then
Select Case Conn_Qulity
Case "Good"
lblqlty.Text = " Good"
Conn_Qulity = "Good"
Case "Intermittent"
lblqlty.Text = " Good"
Conn_Qulity = "Good"
Case "Bad"
lblqlty.Text = " Intermittent"
Conn_Qulity = "Intermittent"
End Select
ElseIf lngFlags And InetConnState.proxy Then
Select Case Conn_Qulity
Case "Good"
lblqlty.Text = " Good"
Conn_Qulity = "Good"
Case "Intermittent"
lblqlty.Text = " Good"
Conn_Qulity = "Good"
Case "Bad"
lblqlty.Text = " Intermittent"
Conn_Qulity = "Intermittent"
End Select
ElseIf lngFlags And InetConnState.ras Then
Select Case Conn_Qulity
Case "Good"
lblqlty.Text = " Good"
Conn_Qulity = "Good"
Case "Intermittent"
lblqlty.Text = " Good"
Conn_Qulity = "Good"
Case "Bad"
lblqlty.Text = " Intermittent"
Conn_Qulity = "Intermittent"
End Select
ElseIf lngFlags And InetConnState.offline Then
Select Case Conn_Qulity
Case "Good"
lblqlty.Text = " Good"
Conn_Qulity = "Good"
Case "Intermittent"
lblqlty.Text = " Good"
Conn_Qulity = "Good"
Case "Bad"
lblqlty.Text = " Intermittent"
Conn_Qulity = "Intermittent"
End Select
End If
Else
' False
Select Case Conn_Qulity
Case "Good"
lblqlty.Text = " Intermittent"
Conn_Qulity = "Intermittent"
Case "Intermittent"
lblqlty.Text = " Bad"
Conn_Qulity = "Bad"
Case "Bad"
lblqlty.Text = " Bad"
Conn_Qulity = "Bad"
End Select
End If
End Function
''' <summary>
''' Timer for the check network quality frequentkly(2000 milli seconds.)
''' </summary>
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
CheckInetConnection()
Application.DoEvents()
Me.Refresh()
End Sub
#End Region
#Region "Buttons Code"
''' <summary>
''' Close Application.
''' </summary>
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Application.Exit()
End Sub
''' <summary>
''' Starts Operations.
''' </summary>
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Call Create_MYIP_Batfile()
Call Handle_NetworkAvailabilityChanged()
End Sub
''' <summary>
''' Force Reconnction Button.
''' </summary>
Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click
Call AppendStatus("Force Disconnction By User.")
Call Re_Connect()
End Sub
#End Region
#Region "Functions"
''' <summary>
''' Delay Methods .., in this code i used Stopwatch for exact Delaytime.
''' </summary>
Public Sub Delay(ByVal Delaytime As Object)
Dim mystopwatch As New Stopwatch
mystopwatch.Start()
Dim mytime As Integer = mystopwatch.ElapsedMilliseconds
Do
If mystopwatch.ElapsedMilliseconds > (mytime + Delaytime) Then
mystopwatch.Stop()
Exit Do
End If
Loop
End Sub
''' <summary>
''' Mail Sending .....
''' </summary>
Public Sub Send_email()
If Not chkdntmail.Checked Then
Dim innlop As Integer
For innlop = 1 To CInt(txtmailretry.Text)
Try
Dim oMsg As System.Net.Mail.MailMessage = New System.Net.Mail.MailMessage()
oMsg.From = New System.Net.Mail.MailAddress("rajeshcragy@yahoo.co.in", "Manage Dialup.")
oMsg.To.Add(New MailAddress(txtemailaddrs.Text, "Manage Dialup."))
oMsg.Subject = "Your Internet Connection Info."
oMsg.Body = " *** IP Address: " & PresentIPAddress & " [At: " & Now.ToString & " ]" & vbCrLf _
& " *** Connection Type: " & lblconntype.Text & vbCrLf _
& " *** Connection Quality: " & lblqlty.Text & vbCrLf & vbCrLf & vbCrLf & vbCrLf & vbCrLf & vbCrLf & vbCrLf & vbCrLf & vbCrLf & vbCrLf _
& " Regards..," & vbCrLf _
& " Rajesh B.., -- A Poor Workman Blames His Tools. --" & vbCrLf _
& " e-mail: rajeshcragy@gmail.com, rajeshcragy@yahoo.co.in." & vbCrLf _
& " Ph: +919397099540" & vbCrLf _
& " Hyderabad, Andra Pradesh, India." & vbCrLf
Dim oSmtp As New SmtpClient("smtp.mail.yahoo.com")
oSmtp.DeliveryMethod = SmtpDeliveryMethod.Network
Dim oCredential As New NetworkCredential("yourmailid", "yourpassword")
oSmtp.UseDefaultCredentials = False
oSmtp.Credentials = oCredential
oSmtp.Send(oMsg)
AppendStatus("Message Sent Successfully!")
Exit For
Catch ex As Exception
AppendStatus(ex.Message)
AppendStatus("Retrinig to Send Mail....")
End Try
Next
End If
End Sub
''' <summary>
''' Records all Status for further Refrrence.
''' </summary>
Public Sub AppendStatus(ByVal MessageText As String)
txtstatus.Items.Add(MessageText & " [At: " & Now.ToString & " ]")
txtstatus.SelectedIndex = txtstatus.Items.Count - 1
End Sub
#End Region
End Class
In this code i covered.., Sending mail from vb.NET, checking the Internet connection quality.