FindUsers and FindChannels support mentions, FindUsers has a channel overload, and less bugs.

src/Discord.Net/DiscordClient.Channels.cs

@@ -84,26 +84,30 @@ namespace Discord
 		public IEnumerable<Channel> FindChannels(Server server, string name, ChannelType type = null, bool exactMatch = false)
 		{
 			if (server == null) throw new ArgumentNullException(nameof(server));
+			if (name == null) throw new ArgumentNullException(nameof(name));
 			CheckReady();
+			
+			var query = server.Channels.Where(x => string.Equals(x.Name, name, StringComparison.OrdinalIgnoreCase));
 
-			IEnumerable<Channel> result;
-			if (!exactMatch && name.StartsWith("#"))
-			{
-				string name2 = name.Substring(1);
-				result = _channels.Where(x => x.Server == server &&
-					string.Equals(x.Name, name, StringComparison.OrdinalIgnoreCase) ||
-					string.Equals(x.Name, name2, StringComparison.OrdinalIgnoreCase));
-			}
-			else
+			if (!exactMatch && name.Length >= 2)
 			{
-				result = _channels.Where(x => x.Server == server &&
-					string.Equals(x.Name, name, StringComparison.OrdinalIgnoreCase));
+				if (name[0] == '<' && name[1] == '#' && name[name.Length - 1] == '>') //Parse mention
+				{					
+					string id = name.Substring(2, name.Length - 3);
+					var channel = _channels[id];
+					if (channel != null)
+						query = query.Concat(new Channel[] { channel });
+				}
+				else if (name[0] == '#') //If we somehow get text starting with # but isn't a mention
+				{
+					string name2 = name.Substring(1);
+					query = query.Concat(server.Channels.Where(x => string.Equals(x.Name, name2, StringComparison.OrdinalIgnoreCase)));
+				}
 			}
 
 			if (type != (string)null)
-				result = result.Where(x => x.Type == type);
-
-			return result;
+				query = query.Where(x => x.Type == type);
+			return query;
 		}
 
 		/// <summary> Creates a new channel with the provided name and type. </summary>

src/Discord.Net/DiscordClient.Users.cs

@@ -141,7 +141,7 @@ namespace Discord
 			return _users[user?.Id, server.Id];
 		}
 
-		/// <summary> Returns all users in with the specified server and name, along with their server-specific data. </summary>
+		/// <summary> Returns all users with the specified server and name, along with their server-specific data. </summary>
 		/// <remarks> Name formats supported: Name and @Name. Search is case-insensitive.</remarks>
 		public IEnumerable<User> FindUsers(Server server, string name, string discriminator = null, bool exactMatch = false)
 		{
@@ -149,16 +149,39 @@ namespace Discord
 			if (name == null) throw new ArgumentNullException(nameof(name));
 			CheckReady();
 
-			IEnumerable<User> query;
-			if (!exactMatch && name.StartsWith("@"))
+			return FindUsers(server.Members, server.Id, name, discriminator, exactMatch);
+		}
+		/// <summary> Returns all users with the specified channel and name, along with their server-specific data. </summary>
+		/// <remarks> Name formats supported: Name and @Name. Search is case-insensitive.</remarks>
+		public IEnumerable<User> FindUsers(Channel channel, string name, string discriminator = null, bool exactMatch = false)
+		{
+			if (channel == null) throw new ArgumentNullException(nameof(channel));
+			if (name == null) throw new ArgumentNullException(nameof(name));
+			CheckReady();
+
+			return FindUsers(channel.Members, channel.IsPrivate ? null : channel.Server.Id, name, discriminator, exactMatch);
+        }
+
+		private IEnumerable<User> FindUsers(IEnumerable<User> users, string serverId, string name, string discriminator = null, bool exactMatch = false)
+		{
+			var query = users.Where(x => string.Equals(x.Name, name, StringComparison.OrdinalIgnoreCase));
+
+			if (!exactMatch && name.Length >= 2)
 			{
-				string name2 = name.Substring(1);
-				query = server.Members.Where(x =>
-					string.Equals(x.Name, name, StringComparison.OrdinalIgnoreCase) ||
-					string.Equals(x.Name, name2, StringComparison.OrdinalIgnoreCase));
+				if (name[0] == '<' && name[1] == '@' && name[name.Length - 1] == '>') //Parse mention
+				{
+					string id = name.Substring(2, name.Length - 3);
+					var channel = _users[id, serverId];
+					if (channel != null)
+						query = query.Concat(new User[] { channel });
+				}
+				else if (name[0] == '@') //If we somehow get text starting with @ but isn't a mention
+				{
+					string name2 = name.Substring(1);
+					query = query.Concat(users.Where(x => string.Equals(x.Name, name2, StringComparison.OrdinalIgnoreCase)));
+				}
 			}
-			else
-				query = server.Members.Where(x => string.Equals(x.Name, name, StringComparison.OrdinalIgnoreCase));
+
 			if (discriminator != null)
 				query = query.Where(x => x.Discriminator == discriminator);
 			return query;