IPAddress.Address Property

The NetworkToHostOrder and HostToNetworkOrder methods require an integer value for input and only output integers.  I'm writing API / pinvoke code and need to be able to marshal a IPAddress value to it's Network order integer value which has nothing to do with comparision operations.  You should add an overload to the coversion functions to take an IPAddress object as an input param.  This is especially true if you're going to make it taboo to use the IPAddress.Address property to retreive the underlying value.

Seems to me that this was marked as obsolete in the early frameworks, but like every useful looking function in the ridiculous .net framework, there is no logical way to get a long value from a dotted IP, hence another intentional brickwall built by MS.

Forget about the built in functions because you will be forced into more silly scenarios such as network byte order, etc. that is designed to eventually make you give up out of frustration!

Solution: (Take note of that word, MS! s-o-l-u-t-i-o-n) After getting the dotted IP address, run it through this function and you should have the correct numeric long value that (backwards thinking .net will understand):

' Use this for .net apps such as socket binding, etc. (the one at the bottom is for the rest of the computer world.)
Public Function IPAddressToNumber_DOTNETSTYLE(ByVal IP_StrValue As String) As Long
    Try
        Dim IPAddress As IPAddress = IPAddress.Parse(IP_StrValue)
            With IPAddress
                Dim IPbyte0 As Long = Convert.ToInt32(IPAddress.GetAddressBytes(3))
                Dim IPbyte1 As Long = Convert.ToInt32(IPAddress.GetAddressBytes(2))
                Dim IPbyte2 As Long = Convert.ToInt32(IPAddress.GetAddressBytes(1))
                Dim IPbyte3 As Long = Convert.ToInt32(IPAddress.GetAddressBytes(0))
                Return ((256 ^ 3) * IPbyte0) + ((256 ^ 2) * IPbyte1) + (256 * IPbyte2) + (IPbyte3)
            End With
                Catch ex As Exception
            Return 0L
    End Try
End Function

' For a Normal Logical Address conversion(which will be backwards in .net but correct for every other scenario in the universe),
' one would actually reverse the byte calculations like the following.

Public Function IPAddressToNumber(ByVal IP_StrValue As String) As Long
    Try
        Dim IPAddress As IPAddress = IPAddress.Parse(IP_StrValue)
            With IPAddress
                Dim IPbyte0 As Long = Convert.ToInt32(IPAddress.GetAddressBytes(0))
                Dim IPbyte1 As Long = Convert.ToInt32(IPAddress.GetAddressBytes(1))
                Dim IPbyte2 As Long = Convert.ToInt32(IPAddress.GetAddressBytes(2))
                Dim IPbyte3 As Long = Convert.ToInt32(IPAddress.GetAddressBytes(3))
                Return ((256 ^ 3) * IPbyte0) + ((256 ^ 2) * IPbyte1) + (256 * IPbyte2) + (IPbyte3)
            End With
                Catch ex As Exception
            Return 0L
    End Try
End Function
' I could list literally thousands of these pitfalls that were created by ms and have never been fixed even since the first .net framework.

This should not be obsolete, because of range validation
private bool NotInRange(string ip, string ipStart, string ipEnd)
    {
        bool result = false;

        System.Net.IPAddress iStart  = System.Net.IPAddress.Parse(ipStart);
        System.Net.IPAddress iEnd   = System.Net.IPAddress.Parse(ipEnd);
        System.Net.IPAddress iToCheck = System.Net.IPAddress.Parse(ip);

        if (iStart.Address <= iToCheck.Address && iEnd.Address >= iToCheck.Address)
        {
            result = true;
        }

        return result;
    }

I'm not entirely convinced this should be marked as obsolete: it's still extremely useful for calculating network ranges based on CIDR notation or when given a subnet mask in the form of an IP address:

IPAddress ip = IPAddress.Parse("192.168.1.151");
IPAddress subnetMask = IPAddress.Parse("255.255.255.192");
IPAddress networkId = new IPAddress(ip.Address & subnetMask.Address);
Console.WriteLine(networkId.ToString()); // will print 192.168.1.128