How to Detect a Dialup Connection?

How to Detect a Dialup Connection?

Author Date Of Submission User Level Sushila D. Patel 05/15/2003 Intermediate http://www.c-sharpcorner.com/Code/2003/May/DetectingDialUpConnection.asp

How to detect if the computer is connected to the net using VB.NET (Windows Form)? How to bring up how can bring up the dial-up window so that the user can dial to the net? (FAQ from the newsgroup)  Introduction:  In the article we'll see how to check connectivity with internet using VB.NET and if its not connected give the client the flexibility to get connected.  Snippet:  To check if there is connection establish to internet we'll write function which returns a boolean value. (true if connected, false if not). We'll need to use the Namespace System.Net.  Dim webreq As HttpWebRequest Dim webresp As HttpWebResponse 'Funtion returns tru or false base on the HttpStatusCode Function checkconnection(ByVal url As String) As Boolean Dim strurl As String = url Dim bConnected As Boolean = False Try webreq = WebRequest.Create(strurl) webresp = webreq.GetResponse If webresp.StatusCode = HttpStatusCode.OK Then bConnected = True Else bConnected = False End If Return bConnected Catch ex As Exception bConnected = False Return bConnected Finally webresp = Nothing End Try End Function As a part of user interface lets have a Textbox (where the user can enter the URL) and Button control. On click of the button we'll check if the client is connected to internet.  If not connected we'll bring up the "Network and Dial-Up Connections" (Here we'll use Shell command)  If connected we'll open the browser window with the URL specified by the client.(We'll use Process class of System.Diagnostics namespace).Here goes the code to be written on button click.  Dim lNg As Integer Dim urlString As String = TextBox1.Text Dim isConnected As Boolean = checkconnection(urlString) If isConnected Then System.Diagnostics.Process.Start("iexplore", urlString) Else Dim ans As String = MsgBox("Do you want to connect?", MsgBoxStyle.YesNo, "No Connected") If ans = vbYes Then lNg = Shell("rundll32.exe shell32.dll,Control_RunDLL ncpa.cpl,,0") Else MsgBox("Sorry canot connect you chose no...") End If End If   Sushila S. Patel, Microsoft .NET MVP

 

 

How to Check if your computer is connected to the Internet?

Author Date Of Submission User Level Simohamed Attahri 08/25/2003 Beginner http://www.c-sharpcorner.com/Code/2003/Aug/CheckInternetConnection.asp

How to check if your computer is connected to the internet with C#. It's much more easier that other tutorials I've seen in other sites. Indeed, we're going to use a simple API function InternetGetConnectedState, to return a boolean variable. This function takes two arguments : The first one is an integer used with out keyword, that means that after calling the function, the variable will contain an interger that describes the connection state ( use of a modem, use of a proxy, offline mode...). Note that you must refer to www.msdn.com for more information about that. The second one is a reserved variable that must be set to 0. In this tutorial, we'll create a class with a static function that returns true if connected and false if not, using our API function in private state. Check this out : using System ; using System.Runtime ; using System.Runtime.InteropServices ; public class InternetCS { //Creating the extern function... [DllImport("wininet.dll")] private extern static bool InternetGetConnectedState( out int Description, int ReservedValue ) ; //Creating a function that uses the API function... public static bool IsConnectedToInternet( ) { int Desc ; return InternetGetConnectedState( out Desc, 0 ) ; } } Simohamed Attahri Simohamed Attahri for help.