C# Signature:

[DllImport("rasapi32.dll",CharSet=CharSet.Auto)]
static extern uint RasDial(
    [In]RASDIALEXTENSIONS lpRasDialExtensions,
    [In]string lpszPhonebook,
    [In]RASDIALPARAMS lpRasDialParams,
    uint dwNotifierType,
    Delegate lpvNotifier,
    ref IntPtr lphRasConn);

VB Signature:

VB.NET,   :)

User-Defined Types:

    [StructLayout(LayoutKind.Sequential)]
    internal class RASDIALEXTENSIONS
    {
        public readonly int dwSize = Marshal.SizeOf(typeof(RASDIALEXTENSIONS));
        public uint dwfOptions = 0;
        public int hwndParent = 0;
        public int reserved = 0;
        public int reserved1 = 0;
        public RASEAPINFO RasEapInfo = new RASEAPINFO();
    }

    [StructLayout(LayoutKind.Sequential,CharSet = CharSet.Auto)]
    internal class RASDIALPARAMS
    {
        public int dwSize = Marshal.SizeOf(typeof(RASDIALPARAMS));
        [MarshalAs(UnmanagedType.ByValTStr,SizeConst =
            (int) RasFieldSizeConstants.RAS_MaxEntryName+1)]
        public string szEntryName = null;
        [MarshalAs(UnmanagedType.ByValTStr,SizeConst =
            (int) RasFieldSizeConstants.RAS_MaxPhoneNumber+1)]
        public string szPhoneNumber = null;
        [MarshalAs(UnmanagedType.ByValTStr,SizeConst =
            (int) RasFieldSizeConstants.RAS_MaxCallbackNumber+1)]
        public string szCallbackNumber = null;
        [MarshalAs(UnmanagedType.ByValTStr,SizeConst =
            (int) RasFieldSizeConstants.UNLEN+1)]
        public string szUserName = null;
        [MarshalAs(UnmanagedType.ByValTStr,SizeConst =
            (int) RasFieldSizeConstants.PWLEN+1)]
        public string szPassword = null;
        [MarshalAs(UnmanagedType.ByValTStr,SizeConst =
            (int) RasFieldSizeConstants.DNLEN+1)]
        public string szDomain = null;
        public int dwSubEntry = 0;
        public int dwCallbackId = 0;
    }

Notes:

Tips & Tricks:

Sample Code:

Alternative Managed API:

Nothing