Quizzer-8: Migrating to .NET 10

Quizzer-8/Quizzer/Extensions/IPAddressExtensions.cs

@@ -0,0 +1,56 @@
+// Original: https://learn.microsoft.com/en-us/archive/blogs/knom/ip-address-calculations-with-c-subnetmasks-networks
+using Microsoft.AspNetCore.HttpOverrides;
+using System.Net;
+
+namespace Quizzer.Extensions
+{
+    public static class IPAddressExtensions
+    {
+        public static IPAddress GetBroadcastAddress(this IPAddress address, IPAddress subnetMask)
+        {
+            byte[] ipAdressBytes = address.GetAddressBytes();
+            byte[] subnetMaskBytes = subnetMask.GetAddressBytes();
+
+            if (ipAdressBytes.Length != subnetMaskBytes.Length)
+                throw new ArgumentException("Lengths of IP address and subnet mask do not match.");
+
+            byte[] broadcastAddress = new byte[ipAdressBytes.Length];
+            for (int i = 0; i < broadcastAddress.Length; i++)
+            {
+                broadcastAddress[i] = (byte)(ipAdressBytes[i] | (subnetMaskBytes[i] ^ 255));
+            }
+            return new IPAddress(broadcastAddress);
+        }
+
+        public static IPAddress GetNetworkAddress(this IPAddress address, IPAddress subnetMask)
+        {
+            byte[] ipAdressBytes = address.GetAddressBytes();
+            byte[] subnetMaskBytes = subnetMask.GetAddressBytes();
+
+            if (ipAdressBytes.Length != subnetMaskBytes.Length)
+                throw new ArgumentException("Lengths of IP address and subnet mask do not match.");
+
+            byte[] broadcastAddress = new byte[ipAdressBytes.Length];
+            for (int i = 0; i < broadcastAddress.Length; i++)
+            {
+                broadcastAddress[i] = (byte)(ipAdressBytes[i] & (subnetMaskBytes[i]));
+            }
+            return new IPAddress(broadcastAddress);
+        }
+
+        /// <summary>
+        /// Are addressA on the same network as addressB ?
+        /// </summary>
+        /// <param name="addressA"></param>
+        /// <param name="addressB"></param>
+        /// <param name="subnetMask"></param>
+        /// <returns>True if A and B are on the same network.</returns>
+        public static bool IsInSameSubnet(this IPAddress addressA, IPAddress addressB, IPAddress subnetMask)
+        {
+            IPAddress networkA = addressA.GetNetworkAddress(subnetMask);
+            IPAddress networkB = addressB.GetNetworkAddress(subnetMask);
+
+            return networkA.Equals(networkB);
+        }
+    }
+}