处理值转换问题

Author: maikebing

ExampleServer/MqttControllers/MqttWeatherForecastController.cs

@@ -1,4 +1,5 @@
 using Microsoft.Extensions.Logging;
+using MQTTnet;
 using MQTTnet.AspNetCore.AttributeRouting;
 using System;
 using System.Threading.Tasks;
@@ -18,24 +19,27 @@ public MqttWeatherForecastController(ILogger<MqttWeatherForecastController> logg
         }
 
         // Supports template routing with typed constraints
-        [MqttRoute("{zipCode:int}/temperature")]
+        [MqttRoute("{zipCode}/temperature")]
         public Task WeatherReport(int zipCode)
         {
             // We have access to the MqttContext
             if (zipCode != 90210) { MqttContext.CloseConnection = true; }
 
             // We have access to the raw message
-            var temperature = BitConverter.ToDouble(Message.Payload);
-
-            _logger.LogInformation($"It's {temperature} degrees in Hollywood");
-
-            // Example validation
-            if (temperature <= 0 || temperature >= 130)
+            if (int.TryParse(Message.ConvertPayloadToString(), out int temperature))
             {
-                return BadMessage();
+                _logger.LogInformation($"It's {temperature} degrees in Hollywood");
+                // Example validation
+                if (temperature <= 0 || temperature >= 130)
+                {
+                    return BadMessage();
+                }
+                else
+                {
+                    return Ok();
+                }
             }
-
-            return Ok();
+            return BadMessage();
         }
     }
 }

ExampleServer/Program.cs

@@ -24,8 +24,8 @@ public static IHostBuilder CreateHostBuilder(string[] args) =>
                 webBuilder.UseKestrel(
                     o =>
                     {
-                        o.ListenAnyIP(50483, l => l.UseMqtt()); // MQTT pipeline
-                        o.ListenAnyIP(50482); // Default HTTP pipeline
+                        o.ListenAnyIP(1883, l => l.UseMqtt()); // MQTT pipeline
+                        o.ListenAnyIP(5000); // Default HTTP pipeline
                     });
                 webBuilder.ConfigureLogging(opts => opts.AddConsole());
                 webBuilder.UseStartup<Startup>();

Source/MQTTnet.AspNetCore.Routing.csproj

@@ -0,0 +1,45 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+	<PropertyGroup>
+		<TargetFrameworks>netstandard2.0;netcoreapp3.1;net5.0;net6.0</TargetFrameworks>
+		<GeneratePackageOnBuild>true</GeneratePackageOnBuild>
+		<Description>
+			This is a support library to integrate AttributeRouting into MQTTnet with AspNetCore.
+
+			Easily create Controllers and Actions to process incoming MQTT messages using attribute-based routing against the incoming message topic.
+		</Description>
+		<Copyright>Copyright (c) Atlas Lift Tech Inc. 2021</Copyright>
+		<PackageLicenseExpression>MIT</PackageLicenseExpression>
+		<PackageTags>MQTT Message Queue Telemetry Transport MQTTClient MQTTServer Server MQTTBroker Broker NETStandard IoT InternetOfThings Messaging Hardware Arduino Sensor Actuator M2M ESP Smart Home Cities Automation Xamarin Blazor AspNetCore</PackageTags>
+		<Company>Atlas Lift Tech Inc.</Company>
+		<Authors>Anton Vishnyak</Authors>
+		<AssemblyVersion>0.3.16</AssemblyVersion>
+		<FileVersion>0.3.16</FileVersion>
+		<LangVersion>default</LangVersion>
+		<RepositoryUrl>https://github.com/Atlas-LiftTech/MQTTnet.AspNetCore.AttributeRouting</RepositoryUrl>
+		<RepositoryType>GIT</RepositoryType>
+		<PackageReleaseNotes>* Added support for passing an array of assemblies to use in route discovery</PackageReleaseNotes>
+		<Version>0.3.16</Version>
+		<PackageRequireLicenseAcceptance>false</PackageRequireLicenseAcceptance>
+		<PackageProjectUrl>https://github.com/Atlas-LiftTech/MQTTnet.AspNetCore.AttributeRouting</PackageProjectUrl>
+		<PublishRepositoryUrl>true</PublishRepositoryUrl>
+		<IncludeSymbols>true</IncludeSymbols>
+		<SymbolPackageFormat>snupkg</SymbolPackageFormat>
+		<EnableNETAnalyzers>true</EnableNETAnalyzers>
+	</PropertyGroup>
+
+	<ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
+		<PackageReference Include="Microsoft.AspNetCore.Http.Connections" Version="1.1.0" />
+	</ItemGroup>
+
+	<ItemGroup Condition="'$(TargetFramework)' == 'netcoreapp3.1'">
+		<FrameworkReference Include="Microsoft.AspNetCore.App" />
+	</ItemGroup>
+
+	<ItemGroup>
+		<PackageReference Include="Microsoft.AspNetCore.Mvc.Core" Version="2.2.5" />
+		<PackageReference Include="Microsoft.Bcl.HashCode" Version="1.1.1" />
+		<PackageReference Include="MQTTnet" Version="4.0.1.184" />
+		<PackageReference Include="MQTTnet.AspNetCore" Version="4.0.1.184" />
+	</ItemGroup>
+</Project>

Source/Routing/MqttRouter.cs

@@ -132,6 +132,7 @@ internal async Task OnIncomingApplicationMessage(IServiceProvider svcProvider, I
                     }
                 }
             }
+ 
         }
 
         private static Task HandlerInvoker(MethodInfo method, object instance, object?[]? parameters)
@@ -173,9 +174,15 @@ private static Task HandlerInvoker(MethodInfo method, object instance, object?[]
 
             if (!param.ParameterType.IsAssignableFrom(value.GetType()))
             {
-                throw new ArgumentException($"Cannot assign type \"{value.GetType()}\" to parameter \"{param.ParameterType.Name} {param.Name}\"", param.Name);
+                try
+                {
+                    value = Convert.ChangeType(value, param.ParameterType);
+                }
+                catch (Exception ex)
+                {
+                    throw new ArgumentException($"Cannot assign type \"{value.GetType()}\" to parameter \"{param.ParameterType.Name} {param.Name}\"", param.Name,ex);
+                }
             }
-
             return value;
         }
     }