fixed .net 5 build

Source/MQTTnet.AspnetCore/Client/Tcp/TcpConnection.cs

@@ -40,7 +40,7 @@ namespace MQTTnet.AspNetCore.Client.Tcp
             _sender = new SocketSender(_socket, PipeScheduler.ThreadPool);
             _receiver = new SocketReceiver(_socket, PipeScheduler.ThreadPool);
         }
-#if NETCOREAPP3_1
+#if NETCOREAPP3_1 || NET5_0
         public override ValueTask DisposeAsync()
 #else
         public Task DisposeAsync()
@@ -53,7 +53,7 @@ namespace MQTTnet.AspNetCore.Client.Tcp
 
             _socket?.Dispose();
 
-#if NETCOREAPP3_1
+#if NETCOREAPP3_1 || NET5_0
 
             return base.DisposeAsync();
         }

Source/MQTTnet.AspnetCore/Extensions/ConnectionRouteBuilderExtensions.cs

@@ -12,6 +12,7 @@ namespace MQTTnet.AspNetCore.Extensions
 #if NETCOREAPP3_1
         [Obsolete("This class is obsolete and will be removed in a future version. The recommended alternative is to use MapMqtt inside Microsoft.AspNetCore.Builder.UseEndpoints(...).")]
 #endif
+#if NETCOREAPP3_1 || NETCOREAPP2_1 || NETSTANDARD
         public static void MapMqtt(this ConnectionsRouteBuilder connection, PathString path)
         {
             connection.MapConnectionHandler<MqttConnectionHandler>(path, options =>
@@ -19,5 +20,6 @@ namespace MQTTnet.AspNetCore.Extensions
                 options.WebSockets.SubProtocolSelector = MqttSubProtocolSelector.SelectSubProtocol;
             });
         }
+#endif
     }
 }

Source/MQTTnet.AspnetCore/Extensions/EndpointRouterExtensions.cs

@@ -1,5 +1,5 @@
 
-#if NETCOREAPP3_1
+#if NETCOREAPP3_1 || NET5_0
 
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Routing;

Source/MQTTnet.AspnetCore/MQTTnet.AspNetCore.csproj

@@ -21,11 +21,11 @@
     <DefineConstants>RELEASE;NETSTANDARD2_0</DefineConstants>
   </PropertyGroup>
 
-  <ItemGroup Condition="'$(TargetFramework)' == 'netcoreapp3.1'">
+  <ItemGroup Condition="'$(TargetFramework)' == 'netcoreapp3.1' or '$(TargetFramework)' == 'net5.0' ">
     <FrameworkReference Include="Microsoft.AspNetCore.App" />
   </ItemGroup>
     
-  <ItemGroup Condition="'$(TargetFramework)' != 'netcoreapp3.1'">
+  <ItemGroup Condition="'$(TargetFramework)' != 'netcoreapp3.1' and '$(TargetFramework)' != 'net5.0' ">
     <PackageReference Include="Microsoft.AspNetCore.Http.Connections" Version="1.1.0" />
   </ItemGroup>
 

Tests/MQTTnet.TestApp.AspNetCore2/Startup.cs

@@ -27,7 +27,7 @@ namespace MQTTnet.TestApp.AspNetCore2
         }
 
         // In class _Startup_ of the ASP.NET Core 3.1 project.
-#if NETCOREAPP3_1
+#if NETCOREAPP3_1 || NET5_0
         public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
         {
             app.UseRouting();