how can i check my network is connected

[Your Code]

how can i check my network is connected, pleaae help me, thanks kevil

[Lost User]

Hi! You can use the sensapi.dll of the internet explorer to check if the network is been connected: Private Declare Function IsNetworkAlive Lib "SENSAPI.DLL" (ByRef lpdwFlags As Long) As Long This is the API declaration to access the IsNetworkAlive function within the sensapi.dll. So, just use it like this: Dim llReturn as Long IF IsNetworkAlive(llReturn) = 0 THEN ' Not connected code ELSE ' ... Your code (if connected) End If If you need more help, just let me know! Marcel Erz -- modified at 2:44 Tuesday 13th December, 2005

[Briga]

If you're under VS2005/FW2 then it's very easy. There's a specific Application event that pop ups whenever network connection status changes.

[Your Code]

please, i need more help, can yuo give me sample kevil

[Lost User]

Hi! Here an other example: Private Declare Function IsNetworkAlive Lib "SENSAPI.DLL" (ByRef lpdwFlags As Long) As Long Private Const NETWORK_ALIVE_LAN = &H1 ' LAN connection Private Const NETWORK_ALIVE_WAN = &H2 ' RAS connection(for internet) Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click Dim llReturn As Long If IsNetworkAlive(llReturn) = 0 Then MessageBox.Show("Your system is not connected!") Else If (llReturn And NETWORK_ALIVE_LAN) = NETWORK_ALIVE_LAN Then MessageBox.Show("Your system is connected to the LAN" + _ " (may be over router to internet too)!") End If If (llReturn And NETWORK_ALIVE_WAN) = NETWORK_ALIVE_WAN Then MessageBox.Show("Your system is connected to the WAN by any" + _ " kind of modem direct connected to you system!") End If End If End Sub If you need more help, just let me know! Marcel Erz

[Steve Pullan]

It has been mentioned that .NET Framework 2.0 has the smarts to do this. Here's a brief rundown on what is required. I found the basis for this post at The Occasionally Connected Application[^]. I just setup a simple one-form app which had one label on it. The label is changed to "Connected" or "Not Connected" depending on the state of the network. The initial state is detected via this code in the Form_Load event ...

Private Sub Form1\_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

    If My.Computer.Network.IsAvailable = True Then
        lblConnectedStatus.Text = "Connected"
    Else
        lblConnectedStatus.Text = "Not Connected"
    End If

End Sub

Now we need to dynamically test the connection state. This is done by creating an event handler for the NetworkAvailabilityChanged in the MyApplication class ...

    Private Sub MyApplication\_NetworkAvailabilityChanged(ByVal sender As Object, ByVal e As Microsoft.VisualBasic.Devices.NetworkAvailableEventArgs) Handles Me.NetworkAvailabilityChanged

        If e.IsNetworkAvailable = True Then

            My.Forms.Form1.lblConnectedStatus.Text = "CONNECTED"

        Else

            My.Forms.Form1.lblConnectedStatus.Text = "Not Connected"

        End If

    End Sub

This passed most of the unplug / disable tests. Use this in conjunction with the new Ping functions in 2.0 and you may have a viable solution. ...Steve "Give a man a fish and you've fed him for a day. Teach him how to fish and you've fed him for life." (Translation: I'll show you the way, but not write the code for you.) I read that somewhere once :-)