عمل dial up connection

here is the code to establish an internet connection from ur C# App

//BEGIN 
InternetConnectionState flags = 0; 
int nConnection = 0; 
bool bInternet = InternetGetConnectedState(ref flags,0); 
if (bInternet == false) 
{ 
 //Not Connected 
 if (flags == 0) 
 { 
   //Do something to tell the user to install some internet connection 
 } 
 int nResult = InternetDial(IntPtr.Zero,"",(int)InternetDialFlags.INTERNET_DIAL_FORCE_PROMPT , ref nConnection , 0); 
 switch(nResult) 
 { 
   case 87://Bad Parameter for InternetDial - Couldn't Connect"; 
     break; 
   case 668://No Connection for InternetDial - Couldn't Connect"; 
     break; 
   case 631://User Cancelled Dialup 
     break; 
   default://Unknown InternetDial Error 
     break; 
   case 0://Connection Succeeded 
     break; 
 } 
 //Do whatever you need to do on the internet (send mail etc) 
 InternetHangup(nConnection,0); 
 //DONE 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 
[DllImport("wininet.dll",CharSet=CharSet.Auto)] 
static extern bool InternetGetConnectedState(ref InternetConnectionState lpdwFlags, int dwReserved); 
[Flags] 
enum InternetConnectionState: int 
{ 
   INTERNET_CONNECTION_MODEM = 0x1, 
   INTERNET_CONNECTION_LAN = 0x2, 
   INTERNET_CONNECTION_PROXY = 0x4, 
   INTERNET_RAS_INSTALLED = 0x10, 
   INTERNET_CONNECTION_OFFLINE = 0x20, 
   INTERNET_CONNECTION_CONFIGURED = 0x40 
} 
[DllImport("wininet.dll",CharSet=CharSet.Auto)] 
static extern int InternetDial(IntPtr hwndParent,[MarshalAs(UnmanagedType.LPStr)] string strConnection,[MarshalAs(UnmanagedType.U4)]int dwFlags,ref int dwConnection,int dwReserved); 
[Flags] 
enum InternetDialFlags: int 
{ 
   INTERNET_DIAL_FORCE_PROMPT    =0x2000, 
   INTERNET_DIAL_SHOW_OFFLINE    =0x4000, 
   INTERNET_DIAL_UNATTENDED      =0x8000 
} 
[DllImport("wininet.dll",CharSet=CharSet.Auto)] 
static extern int InternetHangup([MarshalAs(UnmanagedType.U4)] int nConnection,[MarshalAs(UnmanagedType.U4)]int dwReserved);