Category: roslyn

RSCG – CopyCat
 
 

Implementation of the Decorator pattern in C# – only for not implemented methods

This is how you can use CopyCat .

The code that you start with is

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net8.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Copycat" Version="0.2.0-beta.1" OutputItemType="Analyzer"   />
  </ItemGroup>
	<PropertyGroup>
		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
	</PropertyGroup>
</Project>

The code that you will use is

using CCDemo;

ICoffee c =new Coffee();
c= new CoffeeWithLogging(c);
await c.Prepare();

namespace CCDemo;

internal interface ICoffee
{
    //for the moment does not work for properties in interface
    //string? Name { get; set; }
    Task<bool> Prepare();

    string[] GetIngredients();
}

namespace CCDemo;
internal class Coffee : ICoffee
{
    public string? Name { get; set; }
    public async Task<bool> Prepare()
    {
        Console.WriteLine("start prepare coffee");
        await Task.Delay(1000);
        Console.WriteLine("finish prepare coffee");
        return true;
    }
    public string[] GetIngredients() => new[] { "water", "coffee" };

}

using Copycat;

namespace CCDemo;
[Decorate]
internal partial class CoffeeWithLogging: ICoffee
{
    [Template]
    private string[] AddLogging(Func<string[]> action)
    {
        try
        {
            Console.WriteLine($"start logging {nameof(action)}  ");
            return action();
        }
        catch (Exception e)
        {
            Console.WriteLine($"exception  {nameof(action)} ");
            throw;
        }
        finally
        {
               Console.WriteLine($"end logging {nameof(action)} ");
        }
    }


    [Template]
    public async Task<bool> AddLogging(Func<Task<bool>> action)       
    {
        try
        {
            Console.WriteLine($"start logging {nameof(action)} ");
            return await action();
        }
        catch (Exception e)
        {
            Console.WriteLine($"exception  {nameof(action)} ");
            throw;
        }
        finally
        {
            Console.WriteLine($"end logging {nameof(action)} ");
        }
    }
}

The code that is generated is

// <auto-generated/>
using Copycat;

namespace CCDemo;
internal partial class CoffeeWithLogging
{
    private CCDemo.ICoffee _decorated;
    public CoffeeWithLogging(CCDemo.ICoffee decorated)
    {
        _decorated = decorated;
    }

    /// <see cref = "CoffeeWithLogging.AddLogging(Func{Task{bool}})"/>
    public async //for the moment does not work for properties in interface
    //string? Name { get; set; }
    Task<bool> Prepare()
    {
        try
        {
            Console.WriteLine($"start logging {nameof(Prepare)} ");
            return await _decorated.Prepare();
        }
        catch (Exception e)
        {
            Console.WriteLine($"exception  {nameof(Prepare)} ");
            throw;
        }
        finally
        {
            Console.WriteLine($"end logging {nameof(Prepare)} ");
        }
    }

    /// <see cref = "CoffeeWithLogging.AddLogging(Func{string[]})"/>
    public string[] GetIngredients()
    {
        try
        {
            Console.WriteLine($"start logging {nameof(GetIngredients)}  ");
            return _decorated.GetIngredients();
        }
        catch (Exception e)
        {
            Console.WriteLine($"exception  {nameof(GetIngredients)} ");
            throw;
        }
        finally
        {
            Console.WriteLine($"end logging {nameof(GetIngredients)} ");
        }
    }
}

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/CopyCat

RSCG – AspectGenerator
 
 

AOP for methods in the same project. Uses interceptors

This is how you can use AspectGenerator .

The code that you start with is

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net8.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="AspectGenerator" Version="0.0.9-preview" OutputItemType="Analyzer"  />
  </ItemGroup>
<PropertyGroup>
    
    <InterceptorsPreviewNamespaces>$(InterceptorsPreviewNamespaces);AspectGenerator</InterceptorsPreviewNamespaces>

    <EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
    <CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
</PropertyGroup>
</Project>

The code that you will use is

using AG;

var p=new Person { FirstName="Ignat", LastName="Andrei" };
var x= p.FullName();
Console.WriteLine(x);   

namespace AG;

internal class Person
{
    public string? FirstName { get; set; }
    public string? LastName { get; set; }
    [Metrics]
    public string FullName()
    {
        return $"{FirstName} {LastName}";
    }
}

using System.Diagnostics;
using AspectGenerator;
namespace AG;

[Aspect(
       // Specify the name of the method used in the 'using' statement
       // that returns an IDisposable object.
       OnUsing = nameof(OnUsing)
       )]
[AttributeUsage(AttributeTargets.Method, Inherited = false, AllowMultiple = false)]
sealed class MetricsAttribute : Attribute
{
    //static readonly ActivitySource _activitySource = new("Sample.Aspect");

    public static Activity? OnUsing(InterceptInfo info)
    {
        Console.WriteLine($"Entering {info.MemberInfo.Name}");
        return null;
        //var data=_activitySource.StartActivity(info.MemberInfo.Name);
        //return data;
    }
}

The code that is generated is

// <auto-generated/>
#pragma warning disable
#nullable enable

using System;

#if AG_GENERATE_API || !AG_NOT_GENERATE_API

namespace AspectGenerator
{
	/// <summary>
	/// <para>Defines an aspect.</para>
	/// <para>Create a new attribute decorated with this attribute to define an aspect.</para>
	/// </summary>
	[AttributeUsage(AttributeTargets.Class, Inherited = false, AllowMultiple = false)]
#if AG_PUBLIC_API
	public
#endif
	sealed class AspectAttribute : Attribute
	{
		public string?   OnInit            { get; set; }
		public string?   OnUsing           { get; set; }
		public string?   OnUsingAsync      { get; set; }
		public string?   OnBeforeCall      { get; set; }
		public string?   OnBeforeCallAsync { get; set; }
		public string?   OnCall            { get; set; }
		public string?   OnAfterCall       { get; set; }
		public string?   OnAfterCallAsync  { get; set; }
		public string?   OnCatch           { get; set; }
		public string?   OnCatchAsync      { get; set; }
		public string?   OnFinally         { get; set; }
		public string?   OnFinallyAsync    { get; set; }
		public string[]? InterceptMethods  { get; set; }
		public bool      UseInterceptType  { get; set; }
		public bool      PassArguments     { get; set; }
		public bool      UseInterceptData  { get; set; }
	}

#if AG_PUBLIC_API
	public
#endif
	enum InterceptType
	{
		OnInit,
		OnUsing,
		OnBeforeCall,
		OnAfterCall,
		OnCatch,
		OnFinally
	}

#if AG_PUBLIC_API
	public
#endif
	enum InterceptResult
	{
		Continue,
		Return,
		ReThrow     = Continue,
		IgnoreThrow = Return
	}

#if AG_PUBLIC_API
	public
#endif
	struct Void
	{
	}

#if AG_PUBLIC_API
	public
#endif
	partial class InterceptInfo
	{
		public object?         Tag;
		public InterceptType   InterceptType;
		public InterceptResult InterceptResult;
		public Exception?      Exception;

		public InterceptInfo?                                        PreviousInfo;
		public System.Reflection.MemberInfo                          MemberInfo;
		public object?[]?                                            MethodArguments;
		public Type                                                  AspectType;
		public System.Collections.Generic.Dictionary<string,object?> AspectArguments;
	}

#if AG_PUBLIC_API
	public
#endif
	partial class InterceptInfo<T> : InterceptInfo
	{
		public T ReturnValue;
	}

#if AG_PUBLIC_API
	public
#endif
	partial struct InterceptData<T>
	{
		public object?         Tag;
		public InterceptType   InterceptType;
		public InterceptResult InterceptResult;
		public Exception?      Exception;

		public InterceptInfo<T>?                                     PreviousInfo;
		public System.Reflection.MemberInfo                          MemberInfo;
		public object?[]?                                            MethodArguments;
		public Type                                                  AspectType;
		public System.Collections.Generic.Dictionary<string,object?> AspectArguments;

		public T ReturnValue;
	}
}

#endif

#if AG_GENERATE_InterceptsLocationAttribute || !AG_NOT_GENERATE_InterceptsLocationAttribute

namespace System.Runtime.CompilerServices
{
	[AttributeUsage(AttributeTargets.Method, AllowMultiple = true)]
	sealed class InterceptsLocationAttribute(string filePath, int line, int character) : Attribute
	{
	}
}

#endif

// <auto-generated/>
#pragma warning disable
#nullable enable

using System;

using SR  = System.Reflection;
using SLE = System.Linq.Expressions;
using SCG = System.Collections.Generic;

namespace AspectGenerator
{
	using AspectGenerator = AspectGenerator;

	static partial class Interceptors
	{
		static SR.MethodInfo GetMethodInfo(SLE.Expression expr)
		{
			return expr switch
			{
				SLE.MethodCallExpression mc => mc.Method,
				_                           => throw new InvalidOperationException()
			};
		}

		static SR.MethodInfo MethodOf<T>(SLE.Expression<Func<T>> func) => GetMethodInfo(func.Body);
		static SR.MethodInfo MethodOf   (SLE.Expression<Action>  func) => GetMethodInfo(func.Body);

		static SR. MemberInfo                 FullName_Interceptor_MemberInfo        = MethodOf(() => default(AG.Person).FullName());
		static SCG.Dictionary<string,object?> FullName_Interceptor_AspectArguments_0 = new()
		{
		};
		//
		/// <summary>
		/// Intercepts AG.Person.FullName().
		/// </summary>
		//
		// Intercepts p.FullName().
		[System.Runtime.CompilerServices.InterceptsLocation(@"D:\gth\RSCG_Examples\v2\rscg_examples\AspectGenerator\src\AG\Program.cs", line: 4, character: 10)]
		//
		[System.Runtime.CompilerServices.CompilerGenerated]
		//[System.Diagnostics.DebuggerStepThrough]
		public static string FullName_Interceptor(this AG.Person __this__)
		{
			// AG.MetricsAttribute
			//
			var __info__0 = new AspectGenerator.InterceptInfo<string>
			{
				MemberInfo      = FullName_Interceptor_MemberInfo,
				AspectType      = typeof(AG.MetricsAttribute),
				AspectArguments = FullName_Interceptor_AspectArguments_0,
			};

			using (AG.MetricsAttribute.OnUsing(__info__0))
			{
				__info__0.ReturnValue = __this__.FullName();
			}

			return __info__0.ReturnValue;
		}
	}
}

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/AspectGenerator

RSCG – mocklis
 
 

Generating mocks from classes for unit tests

This is how you can use mocklis .

The code that you start with is

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <TargetFramework>net8.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>

    <IsPackable>false</IsPackable>
    <IsTestProject>true</IsTestProject>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.9.0-preview-23577-04" />
    <PackageReference Include="Mocklis" Version="1.4.0-alpha.2" />
    <PackageReference Include="MSTest.TestAdapter" Version="3.2.0-preview.23623.1" />
    <PackageReference Include="MSTest.TestFramework" Version="3.2.0-preview.23623.1" />
    <PackageReference Include="coverlet.collector" Version="6.0.0">
      <PrivateAssets>all</PrivateAssets>
      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
    </PackageReference>
  </ItemGroup>

  <ItemGroup>
    <ProjectReference Include="..\MockLisClock\MockLisClock.csproj" />
  </ItemGroup>
	<PropertyGroup>
		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
	</PropertyGroup>

</Project>

The code that you will use is

namespace TestClock;

[MocklisClass]
public partial class TestMock : IMyClock
{

}

using Mocklis;

namespace TestClock;

[TestClass]
public class TestClock
{
    [TestMethod]
    public void TestMyClock()
    {
        var mockSetup = new TestMock();
        mockSetup.GetNow.Return(DateTime.Now.AddYears(-1));

        // When testing the mock like this you need to cast to the interface.
        // This is different from e.g. Moq where the mocked instance and the 'programming interface' are different things.
        // With Mocklis they are the same. The 99% case is where the mock is passed to another constructor as a dependency,
        // in which case there's an implicit cast to the interface.
        var mock = (IMyClock)mockSetup;
        var data = mock.GetNow();
        Assert.AreEqual(DateTime.Now.Year - 1, data.Year);

    }
}

global using Microsoft.VisualStudio.TestTools.UnitTesting;
global using MockTest;
global using Mocklis.Core;

The code that is generated is

// <auto-generated />

#nullable enable

namespace TestClock
{
    partial class TestMock
    {
        public global::Mocklis.Core.FuncMethodMock<global::System.DateTime> GetNow { get; }

        global::System.DateTime global::MockTest.IMyClock.GetNow() => GetNow.Call();

        public global::Mocklis.Core.FuncMethodMock<global::System.DateTime> GetUtcNow { get; }

        global::System.DateTime global::MockTest.IMyClock.GetUtcNow() => GetUtcNow.Call();

        public TestMock() : base()
        {
            this.GetNow = new global::Mocklis.Core.FuncMethodMock<global::System.DateTime>(this, "TestMock", "IMyClock", "GetNow", "GetNow", global::Mocklis.Core.Strictness.Lenient);
            this.GetUtcNow = new global::Mocklis.Core.FuncMethodMock<global::System.DateTime>(this, "TestMock", "IMyClock", "GetUtcNow", "GetUtcNow", global::Mocklis.Core.Strictness.Lenient);
        }
    }
}

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/mocklis

RSCG – RSCG_UtilityTypes
 
 

Add omit and pick to selectively generate types from existing types

This is how you can use RSCG_UtilityTypes .

The code that you start with is

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net8.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>
  <ItemGroup>
	  <PackageReference Include="RSCG_UtilityTypes" Version="2023.1223.1230" OutputItemType="Analyzer" ReferenceOutputAssembly="false" />
	  <PackageReference Include="RSCG_UtilityTypesCommon" Version="2023.1223.1230" />
  </ItemGroup>
	<PropertyGroup>
		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
	</PropertyGroup>
</Project>

The code that you will use is

using UtilDemo;

var p=new PersonFull();
p.FirstName="Andrei";
p.LastName="Ignat";
Person1 p1=(Person1)p ;
Person2 p2=(Person2)p ;
Console.WriteLine(p1.FirstName);
Console.WriteLine(p2.LastName);

using RSCG_UtilityTypesCommon;

namespace UtilDemo;
[Pick("Person1",nameof(FirstName),nameof(LastName))]
[Omit("Person2", nameof(Salary))]
public class PersonFull
{
    public string FirstName { get; set; }
    public string LastName { get; set; }
    public int Salary { get; set; }

}

The code that is generated is

namespace UtilDemo
{
partial class Person1
    {
        public string FirstName { get; set; }
        public string LastName { get; set; }

public static explicit operator Person1(PersonFull data )
    {
        var ret= new Person1 ();
        ret.FirstName = data.FirstName;
ret.LastName = data.LastName;
        return ret;
    }



public static explicit operator PersonFull(Person1 data )
    {
        var ret= new PersonFull ();
        ret.FirstName = data.FirstName;
ret.LastName = data.LastName;
        return ret;
    }


}
}

namespace UtilDemo
{
partial class Person2
    {
        public string FirstName { get; set; }
        public string LastName { get; set; }

public static explicit operator Person2(PersonFull data )
    {
        var ret= new Person2 ();
        ret.FirstName = data.FirstName;
ret.LastName = data.LastName;
        return ret;
    }



public static explicit operator PersonFull(Person2 data )
    {
        var ret= new PersonFull ();
        ret.FirstName = data.FirstName;
ret.LastName = data.LastName;
        return ret;
    }


}
}

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/RSCG_UtilityTypes

RSCG – Ling.Audit
 
 

Generating audit data from class implementation of interfaces

This is how you can use Ling.Audit .

The code that you start with is

<Project Sdk="Microsoft.NET.Sdk">

  <PropertyGroup>
    <OutputType>Exe</OutputType>
    <TargetFramework>net8.0</TargetFramework>
    <ImplicitUsings>enable</ImplicitUsings>
    <Nullable>enable</Nullable>
  </PropertyGroup>

  <ItemGroup>
    <PackageReference Include="Ling.Audit" Version="1.1.0" />
  </ItemGroup>
	<PropertyGroup>
		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles>
		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath>
	</PropertyGroup>
</Project>

The code that you will use is

// See https://aka.ms/new-console-template for more information
using LingDemo;

Console.WriteLine("Hello, World!");
var p = new Person();
await Task.Delay(2000);
p.FirstName = "Andrei";
p.LastName = "Ignat";
Console.WriteLine(p.CreationTime);
Console.WriteLine(p.LastModificationTime);

using Ling.Audit;

namespace LingDemo;
partial class Person :IFullAudited<Guid>
{
    public int ID { get; set; }
    public string FirstName { get; set; }= string.Empty;
    public string LastName { get; set; } = string.Empty;
}

The code that is generated is

// <auto-generated/>

#nullable enable annotations
#nullable disable warnings

namespace LingDemo
{
    partial class Person
    {
        /// <summary>
        /// Gets or sets the creation time of this entity.
        /// </summary>
        public virtual global::System.DateTimeOffset CreationTime { get; set; }
    
        /// <summary>
        /// Gets or sets the creator Id of this entity.
        /// </summary>
        public virtual global::System.Nullable<global::System.Guid> CreatorId { get; set; }
    
        /// <summary>
        /// Gets or sets the last modification time of this entity.
        /// </summary>
        public virtual global::System.Nullable<global::System.DateTimeOffset> LastModificationTime { get; set; }
    
        /// <summary>
        /// Gets or sets the last modifier Id of this entity.
        /// </summary>
        public virtual global::System.Nullable<global::System.Guid> LastModifierId { get; set; }
    
        /// <summary>
        /// Gets or sets whether this entity is soft deleted.
        /// </summary>
        public virtual global::System.Boolean IsDeleted { get; set; }
    
        /// <summary>
        /// Gets or sets the deletion time of this entity.
        /// </summary>
        public virtual global::System.Nullable<global::System.DateTimeOffset> DeletionTime { get; set; }
    
        /// <summary>
        /// Get or set the deleter Id of this entity.
        /// </summary>
        public virtual global::System.Nullable<global::System.Guid> DeleterId { get; set; }
    }
}

Code and pdf at

https://ignatandrei.github.io/RSCG_Examples/v2/docs/Ling.Audit

RSCG – Com    

Generating Com Declarations

This is how you can use Com .

The code that you start with is

  <Project Sdk="Microsoft.NET.Sdk">    <PropertyGroup>     <OutputType>Exe</OutputType>     <TargetFramework>net8.0</TargetFramework>     <ImplicitUsings>enable</ImplicitUsings>     <Nullable>enable</Nullable> 	  <AllowUnsafeBlocks>true</AllowUnsafeBlocks> <!--
<PackageReference Include="System.Runtime.InteropServices" />
-->   </PropertyGroup> 	<PropertyGroup> 		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles> 		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath> 	</PropertyGroup> </Project>   

The code that you will use is

  using test;  IShellExecute shellExecute = new ShellExecuteClass();  // Open a file using the default associated program IntPtr result = shellExecute.ShellExecute(     IntPtr.Zero, // HWND (handle to parent window)     "open",      // Operation to perform     "notepad.exe", // File to open (replace with your file or URL)     "",           // Parameters     "",           // Working directory     1            // Show command (SW_SHOWNORMAL) );  Console.WriteLine($"ShellExecute Result: {result}");   

  using System; using System.Runtime.InteropServices; using System.Runtime.InteropServices.Marshalling;  namespace test;  // Import the ShellExecute function from Shell32.dll using ComImport [ComImport] [Guid("00000000-0000-0000-C000-000000000046")] [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)] public interface IUnknown {     void QueryInterface(ref Guid riid, out IntPtr ppvObject);     void AddRef();     void Release(); }  //[ComImport] [GeneratedComInterface(StringMarshalling = StringMarshalling.Utf8)] [Guid("000214F9-0000-0000-C000-000000000046")] [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)] public partial interface IShellExecute {     IntPtr ShellExecute(IntPtr hwnd, string lpOperation, string lpFile, string lpParameters, string lpDirectory, int nShowCmd); }   // Replace this with your actual ShellExecute COM class public class ShellExecuteClass : IShellExecute {     public IntPtr ShellExecute(IntPtr hwnd, string lpOperation, string lpFile, string lpParameters, string lpDirectory, int nShowCmd)     {         // Implement the ShellExecute functionality         return NativeMethods.ShellExecute(hwnd, lpOperation, lpFile, lpParameters, lpDirectory, nShowCmd);     } }  // NativeMethods class to import necessary functions from Shell32.dll static class NativeMethods {     [DllImport("shell32.dll", CharSet = CharSet.Unicode, SetLastError = true)]     public static extern IntPtr ShellExecute(         IntPtr hwnd,         string lpOperation,         string lpFile,         string lpParameters,         string lpDirectory,         int nShowCmd     ); }   

  The code that is generated is

 // <auto-generated /> #pragma warning disable CS0612, CS0618 file unsafe class InterfaceInformation : global::System.Runtime.InteropServices.Marshalling.IIUnknownInterfaceType {     public static global::System.Guid Iid { get; } = new(new global::System.ReadOnlySpan<byte>(new byte[] { 249, 20, 2, 0, 0, 0, 0, 0, 192, 0, 0, 0, 0, 0, 0, 70 }));      private static void** _vtable;     public static void** ManagedVirtualMethodTable => _vtable != null ? _vtable : (_vtable = InterfaceImplementation.CreateManagedVirtualFunctionTable()); }  [global::System.Runtime.InteropServices.DynamicInterfaceCastableImplementationAttribute] file unsafe partial interface InterfaceImplementation : global::test.IShellExecute {     [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.Interop.ComInterfaceGenerator", "8.0.9.3103")]     [global::System.Runtime.CompilerServices.SkipLocalsInitAttribute]     nint global::test.IShellExecute.ShellExecute(nint hwnd, string lpOperation, string lpFile, string lpParameters, string lpDirectory, int nShowCmd)     {         var(__this, __vtable_native) = ((global::System.Runtime.InteropServices.Marshalling.IUnmanagedVirtualMethodTableProvider)this).GetVirtualMethodTableInfoForKey(typeof(global::test.IShellExecute));         byte* __lpOperation_native = default;         byte* __lpFile_native = default;         byte* __lpParameters_native = default;         byte* __lpDirectory_native = default;         nint __retVal = default;         int __invokeRetVal = default;         // Setup - Perform required setup.         scoped global::System.Runtime.InteropServices.Marshalling.Utf8StringMarshaller.ManagedToUnmanagedIn __lpDirectory_native__marshaller = new();         scoped global::System.Runtime.InteropServices.Marshalling.Utf8StringMarshaller.ManagedToUnmanagedIn __lpParameters_native__marshaller = new();         scoped global::System.Runtime.InteropServices.Marshalling.Utf8StringMarshaller.ManagedToUnmanagedIn __lpFile_native__marshaller = new();         scoped global::System.Runtime.InteropServices.Marshalling.Utf8StringMarshaller.ManagedToUnmanagedIn __lpOperation_native__marshaller = new();         try         {             // Marshal - Convert managed data to native data.             __lpDirectory_native__marshaller.FromManaged(lpDirectory, stackalloc byte[global::System.Runtime.InteropServices.Marshalling.Utf8StringMarshaller.ManagedToUnmanagedIn.BufferSize]);             __lpParameters_native__marshaller.FromManaged(lpParameters, stackalloc byte[global::System.Runtime.InteropServices.Marshalling.Utf8StringMarshaller.ManagedToUnmanagedIn.BufferSize]);             __lpFile_native__marshaller.FromManaged(lpFile, stackalloc byte[global::System.Runtime.InteropServices.Marshalling.Utf8StringMarshaller.ManagedToUnmanagedIn.BufferSize]);             __lpOperation_native__marshaller.FromManaged(lpOperation, stackalloc byte[global::System.Runtime.InteropServices.Marshalling.Utf8StringMarshaller.ManagedToUnmanagedIn.BufferSize]);             {                 // PinnedMarshal - Convert managed data to native data that requires the managed data to be pinned.                 __lpDirectory_native = __lpDirectory_native__marshaller.ToUnmanaged();                 __lpParameters_native = __lpParameters_native__marshaller.ToUnmanaged();                 __lpFile_native = __lpFile_native__marshaller.ToUnmanaged();                 __lpOperation_native = __lpOperation_native__marshaller.ToUnmanaged();                 __invokeRetVal = ((delegate* unmanaged[MemberFunction]<void*, nint, byte*, byte*, byte*, byte*, int, nint*, int> )__vtable_native[3])(__this, hwnd, __lpOperation_native, __lpFile_native, __lpParameters_native, __lpDirectory_native, nShowCmd, &__retVal);             }              // NotifyForSuccessfulInvoke - Keep alive any managed objects that need to stay alive across the call.             global::System.Runtime.InteropServices.Marshal.ThrowExceptionForHR(__invokeRetVal);             global::System.GC.KeepAlive(this);         }         finally         {             // CleanupCallerAllocated - Perform cleanup of caller allocated resources.             __lpDirectory_native__marshaller.Free();             __lpParameters_native__marshaller.Free();             __lpFile_native__marshaller.Free();             __lpOperation_native__marshaller.Free();         }          return __retVal;     } }  file unsafe partial interface InterfaceImplementation {     [global::System.Runtime.InteropServices.UnmanagedCallersOnlyAttribute(CallConvs = new[] { typeof(global::System.Runtime.CompilerServices.CallConvMemberFunction) })]     internal static int ABI_ShellExecute(global::System.Runtime.InteropServices.ComWrappers.ComInterfaceDispatch* __this_native, nint hwnd, byte* __lpOperation_native, byte* __lpFile_native, byte* __lpParameters_native, byte* __lpDirectory_native, int nShowCmd, nint* __invokeRetValUnmanaged__param)     {         global::test.IShellExecute @this = default;         string lpOperation = default;         string lpFile = default;         string lpParameters = default;         string lpDirectory = default;         ref nint __invokeRetValUnmanaged = ref *__invokeRetValUnmanaged__param;         nint __invokeRetVal = default;         int __retVal = default;         try         {             // Unmarshal - Convert native data to managed data.             lpDirectory = global::System.Runtime.InteropServices.Marshalling.Utf8StringMarshaller.ConvertToManaged(__lpDirectory_native);             lpParameters = global::System.Runtime.InteropServices.Marshalling.Utf8StringMarshaller.ConvertToManaged(__lpParameters_native);             lpFile = global::System.Runtime.InteropServices.Marshalling.Utf8StringMarshaller.ConvertToManaged(__lpFile_native);             lpOperation = global::System.Runtime.InteropServices.Marshalling.Utf8StringMarshaller.ConvertToManaged(__lpOperation_native);             @this = global::System.Runtime.InteropServices.ComWrappers.ComInterfaceDispatch.GetInstance<global::test.IShellExecute>(__this_native);             __invokeRetVal = @this.ShellExecute(hwnd, lpOperation, lpFile, lpParameters, lpDirectory, nShowCmd);             // NotifyForSuccessfulInvoke - Keep alive any managed objects that need to stay alive across the call.             __retVal = 0; // S_OK             // Marshal - Convert managed data to native data.             __invokeRetValUnmanaged = __invokeRetVal;         }         catch (global::System.Exception __exception)         {             __retVal = global::System.Runtime.InteropServices.Marshalling.ExceptionAsHResultMarshaller<int>.ConvertToUnmanaged(__exception);         }          return __retVal;     } }  file unsafe partial interface InterfaceImplementation {     internal static void** CreateManagedVirtualFunctionTable()     {         void** vtable = (void**)global::System.Runtime.CompilerServices.RuntimeHelpers.AllocateTypeAssociatedMemory(typeof(global::test.IShellExecute), sizeof(void*) * 4);         {             nint v0, v1, v2;             global::System.Runtime.InteropServices.ComWrappers.GetIUnknownImpl(out v0, out v1, out v2);             vtable[0] = (void*)v0;             vtable[1] = (void*)v1;             vtable[2] = (void*)v2;         }          {             vtable[3] = (void*)(delegate* unmanaged[MemberFunction]<global::System.Runtime.InteropServices.ComWrappers.ComInterfaceDispatch*, nint, byte*, byte*, byte*, byte*, int, nint*, int> )&ABI_ShellExecute;         }          return vtable;     } }  namespace test {     [global::System.Runtime.InteropServices.Marshalling.IUnknownDerivedAttribute<InterfaceInformation, InterfaceImplementation>]     public partial interface IShellExecute     {     } }  namespace test {     public partial interface IShellExecute     {     } } 

Code and pdf at https://ignatandrei.github.io/RSCG_Examples/v2/docs/Com

RSCG – RDG    

Generating replacing for minimal API Map

This is how you can use RDG .

The code that you start with is

  <Project Sdk="Microsoft.NET.Sdk.Web">  	<PropertyGroup> 		<TargetFramework>net8.0</TargetFramework> 		<Nullable>enable</Nullable> 		<ImplicitUsings>enable</ImplicitUsings> 		<InvariantGlobalization>true</InvariantGlobalization> 	</PropertyGroup>  	<ItemGroup> 		<!--
		<PackageReference Include="Microsoft.Extensions.Http"></PackageReference>
		--> 		<PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="8.0.0" /> 		<PackageReference Include="Swashbuckle.AspNetCore" Version="6.4.0" /> 	</ItemGroup>  	<PropertyGroup> 		<EnableRequestDelegateGenerator>true</EnableRequestDelegateGenerator> 	</PropertyGroup>   	<PropertyGroup> 		<EmitCompilerGeneratedFiles>true</EmitCompilerGeneratedFiles> 		<CompilerGeneratedFilesOutputPath>$(BaseIntermediateOutputPath)\GX</CompilerGeneratedFilesOutputPath> 	</PropertyGroup> </Project>   

The code that you will use is

  var builder = WebApplication.CreateBuilder(args);  // Add services to the container. // Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle builder.Services.AddEndpointsApiExplorer(); builder.Services.AddSwaggerGen();  var app = builder.Build();  // Configure the HTTP request pipeline. if (app.Environment.IsDevelopment()) {     app.UseSwagger();     app.UseSwaggerUI(); }  var summaries = new[] {     "Freezing", "Bracing", "Chilly", "Cool", "Mild", "Warm", "Balmy", "Hot", "Sweltering", "Scorching" };  app.MapGet("/weatherforecast", () => {     var forecast = Enumerable.Range(1, 5).Select(index =>         new WeatherForecast         (             DateOnly.FromDateTime(DateTime.Now.AddDays(index)),             Random.Shared.Next(-20, 55),             summaries[Random.Shared.Next(summaries.Length)]         ))         .ToArray();     return forecast; }) .WithName("GetWeatherForecast") .WithOpenApi();  app.Run();  internal record WeatherForecast(DateOnly Date, int TemperatureC, string? Summary) {     public int TemperatureF => 32 + (int)(TemperatureC / 0.5556); }   

  The code that is generated is

 //------------------------------------------------------------------------------ // <auto-generated> //     This code was generated by a tool. // //     Changes to this file may cause incorrect behavior and will be lost if //     the code is regenerated. // </auto-generated> //------------------------------------------------------------------------------ #nullable enable  namespace System.Runtime.CompilerServices {     [System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.AspNetCore.Http.RequestDelegateGenerator, Version=8.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60", "8.0.0.0")]     [AttributeUsage(AttributeTargets.Method, AllowMultiple = true)]     file sealed class InterceptsLocationAttribute : Attribute     {         public InterceptsLocationAttribute(string filePath, int line, int column)         {         }     } }  namespace Microsoft.AspNetCore.Http.Generated {     using System;     using System.Collections;     using System.Collections.Generic;     using System.Collections.ObjectModel;     using System.Diagnostics;     using System.Diagnostics.CodeAnalysis;     using System.Globalization;     using System.Linq;     using System.Reflection;     using System.Runtime.CompilerServices;     using System.Text.Json;     using System.Text.Json.Serialization.Metadata;     using System.Threading.Tasks;     using System.IO;     using Microsoft.AspNetCore.Antiforgery;     using Microsoft.AspNetCore.Routing;     using Microsoft.AspNetCore.Routing.Patterns;     using Microsoft.AspNetCore.Builder;     using Microsoft.AspNetCore.Http;     using Microsoft.AspNetCore.Http.Json;     using Microsoft.AspNetCore.Http.Metadata;     using Microsoft.Extensions.DependencyInjection;     using Microsoft.Extensions.FileProviders;     using Microsoft.Extensions.Logging;     using Microsoft.Extensions.Primitives;     using Microsoft.Extensions.Options;      using MetadataPopulator = System.Func<System.Reflection.MethodInfo, Microsoft.AspNetCore.Http.RequestDelegateFactoryOptions?, Microsoft.AspNetCore.Http.RequestDelegateMetadataResult>;     using RequestDelegateFactoryFunc = System.Func<System.Delegate, Microsoft.AspNetCore.Http.RequestDelegateFactoryOptions, Microsoft.AspNetCore.Http.RequestDelegateMetadataResult?, Microsoft.AspNetCore.Http.RequestDelegateResult>;      [System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.AspNetCore.Http.RequestDelegateGenerator, Version=8.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60", "8.0.0.0")]     file static class GeneratedRouteBuilderExtensionsCore     {         private static readonly JsonOptions FallbackJsonOptions = new();         private static readonly string[] GetVerb = new[] { global::Microsoft.AspNetCore.Http.HttpMethods.Get };          [InterceptsLocation(@"D:\gth\RSCG_Examples\v2\rscg_examples\RDG\src\RDGDemo\RDGDemoWebApi\Program.cs", 22, 5)]         internal static RouteHandlerBuilder MapGet0(             this IEndpointRouteBuilder endpoints,             [StringSyntax("Route")] string pattern,             Delegate handler)         {             MetadataPopulator populateMetadata = (methodInfo, options) =>             {                 Debug.Assert(options != null, "RequestDelegateFactoryOptions not found.");                 Debug.Assert(options.EndpointBuilder != null, "EndpointBuilder not found.");                 options.EndpointBuilder.Metadata.Add(new System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.AspNetCore.Http.RequestDelegateGenerator, Version=8.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60", "8.0.0.0"));                 options.EndpointBuilder.Metadata.Add(new ProducesResponseTypeMetadata(statusCode: StatusCodes.Status200OK, type: typeof(global::WeatherForecast[]), contentTypes: GeneratedMetadataConstants.JsonContentType));                 return new RequestDelegateMetadataResult { EndpointMetadata = options.EndpointBuilder.Metadata.AsReadOnly() };             };             RequestDelegateFactoryFunc createRequestDelegate = (del, options, inferredMetadataResult) =>             {                 Debug.Assert(options != null, "RequestDelegateFactoryOptions not found.");                 Debug.Assert(options.EndpointBuilder != null, "EndpointBuilder not found.");                 Debug.Assert(options.EndpointBuilder.ApplicationServices != null, "ApplicationServices not found.");                 Debug.Assert(options.EndpointBuilder.FilterFactories != null, "FilterFactories not found.");                 var handler = Cast(del, global::WeatherForecast[] () => throw null!);                 EndpointFilterDelegate? filteredInvocation = null;                 var serviceProvider = options.ServiceProvider ?? options.EndpointBuilder.ApplicationServices;                 var jsonOptions = serviceProvider?.GetService<IOptions<JsonOptions>>()?.Value ?? FallbackJsonOptions;                 var jsonSerializerOptions = jsonOptions.SerializerOptions;                 jsonSerializerOptions.MakeReadOnly();                 var objectJsonTypeInfo = (JsonTypeInfo<object?>)jsonSerializerOptions.GetTypeInfo(typeof(object));                 var responseJsonTypeInfo =  (JsonTypeInfo<global::WeatherForecast&#91;&#93;?>)jsonSerializerOptions.GetTypeInfo(typeof(global::WeatherForecast[]));                  if (options.EndpointBuilder.FilterFactories.Count > 0)                 {                     filteredInvocation = GeneratedRouteBuilderExtensionsCore.BuildFilterDelegate(ic =>                     {                         if (ic.HttpContext.Response.StatusCode == 400)                         {                             return ValueTask.FromResult<object?>(Results.Empty);                         }                         return ValueTask.FromResult<object?>(handler());                     },                     options.EndpointBuilder,                     handler.Method);                 }                  Task RequestHandler(HttpContext httpContext)                 {                     var wasParamCheckFailure = false;                     if (wasParamCheckFailure)                     {                         httpContext.Response.StatusCode = 400;                         return Task.CompletedTask;                     }                     var result = handler();                     return GeneratedRouteBuilderExtensionsCore.WriteJsonResponseAsync(httpContext.Response, result, responseJsonTypeInfo);                 }                  async Task RequestHandlerFiltered(HttpContext httpContext)                 {                     var wasParamCheckFailure = false;                     if (wasParamCheckFailure)                     {                         httpContext.Response.StatusCode = 400;                     }                     var result = await filteredInvocation(EndpointFilterInvocationContext.Create(httpContext));                     if (result is not null)                     {                         await GeneratedRouteBuilderExtensionsCore.ExecuteReturnAsync(result, httpContext, objectJsonTypeInfo);                     }                 }                  RequestDelegate targetDelegate = filteredInvocation is null ? RequestHandler : RequestHandlerFiltered;                 var metadata = inferredMetadataResult?.EndpointMetadata ?? ReadOnlyCollection<object>.Empty;                 return new RequestDelegateResult(targetDelegate, metadata);             };             return MapCore(                 endpoints,                 pattern,                 handler,                 GetVerb,                 populateMetadata,                 createRequestDelegate);         }            internal static RouteHandlerBuilder MapCore(             this IEndpointRouteBuilder routes,             string pattern,             Delegate handler,             IEnumerable<string>? httpMethods,             MetadataPopulator populateMetadata,             RequestDelegateFactoryFunc createRequestDelegate)         {             return RouteHandlerServices.Map(routes, pattern, handler, httpMethods, populateMetadata, createRequestDelegate);         }          private static T Cast<T>(Delegate d, T _) where T : Delegate         {             return (T)d;         }          private static EndpointFilterDelegate BuildFilterDelegate(EndpointFilterDelegate filteredInvocation, EndpointBuilder builder, MethodInfo mi)         {             var routeHandlerFilters =  builder.FilterFactories;             var context0 = new EndpointFilterFactoryContext             {                 MethodInfo = mi,                 ApplicationServices = builder.ApplicationServices,             };             var initialFilteredInvocation = filteredInvocation;             for (var i = routeHandlerFilters.Count - 1; i >= 0; i--)             {                 var filterFactory = routeHandlerFilters[i];                 filteredInvocation = filterFactory(context0, filteredInvocation);             }             return filteredInvocation;         }          private static Task ExecuteReturnAsync(object? obj, HttpContext httpContext, JsonTypeInfo<object?> jsonTypeInfo)         {             if (obj is IResult r)             {                 return r.ExecuteAsync(httpContext);             }             else if (obj is string s)             {                 return httpContext.Response.WriteAsync(s);             }             else             {                 return WriteJsonResponseAsync(httpContext.Response, obj, jsonTypeInfo);             }         }          [UnconditionalSuppressMessage("Trimming", "IL2026:RequiresUnreferencedCode",             Justification = "The 'JsonSerializer.IsReflectionEnabledByDefault' feature switch, which is set to false by default for trimmed ASP.NET apps, ensures the JsonSerializer doesn't use Reflection.")]         [UnconditionalSuppressMessage("AOT", "IL3050:RequiresDynamicCode", Justification = "See above.")]         private static Task WriteJsonResponseAsync<T>(HttpResponse response, T? value, JsonTypeInfo<T?> jsonTypeInfo)         {             var runtimeType = value?.GetType();              if (jsonTypeInfo.ShouldUseWith(runtimeType))             {                 return HttpResponseJsonExtensions.WriteAsJsonAsync(response, value, jsonTypeInfo, default);             }              return response.WriteAsJsonAsync<object?>(value, jsonTypeInfo.Options);         }          private static bool HasKnownPolymorphism(this JsonTypeInfo jsonTypeInfo)             => jsonTypeInfo.Type.IsSealed || jsonTypeInfo.Type.IsValueType || jsonTypeInfo.PolymorphismOptions is not null;          private static bool ShouldUseWith(this JsonTypeInfo jsonTypeInfo, [NotNullWhen(false)] Type? runtimeType)             => runtimeType is null || jsonTypeInfo.Type == runtimeType || jsonTypeInfo.HasKnownPolymorphism();       }      [System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.AspNetCore.Http.RequestDelegateGenerator, Version=8.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60", "8.0.0.0")]     file static class GeneratedMetadataConstants     {         public static readonly string[] JsonContentType = new [] { "application/json" };         public static readonly string[] PlaintextContentType = new [] { "text/plain" };         public static readonly string[] FormFileContentType = new[] { "multipart/form-data" };         public static readonly string[] FormContentType = new[] { "multipart/form-data", "application/x-www-form-urlencoded" };     }       [System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.AspNetCore.Http.RequestDelegateGenerator, Version=8.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60", "8.0.0.0")]     file sealed class LogOrThrowExceptionHelper     {         private readonly ILogger? _rdgLogger;         private readonly bool _shouldThrow;          public LogOrThrowExceptionHelper(IServiceProvider? serviceProvider, RequestDelegateFactoryOptions? options)         {             var loggerFactory = serviceProvider?.GetRequiredService<ILoggerFactory>();             _rdgLogger = loggerFactory?.CreateLogger("Microsoft.AspNetCore.Http.RequestDelegateGenerator.RequestDelegateGenerator");             _shouldThrow = options?.ThrowOnBadRequest ?? false;         }          public void RequestBodyIOException(IOException exception)         {             if (_rdgLogger != null)             {                 _requestBodyIOException(_rdgLogger, exception);             }         }          private static readonly Action<ILogger, Exception?> _requestBodyIOException =             LoggerMessage.Define(LogLevel.Debug, new EventId(1, "RequestBodyIOException"), "Reading the request body failed with an IOException.");          public void InvalidJsonRequestBody(string parameterTypeName, string parameterName, Exception exception)         {             if (_shouldThrow)             {                 var message = string.Format(CultureInfo.InvariantCulture, "Failed to read parameter \"{0} {1}\" from the request body as JSON.", parameterTypeName, parameterName);                 throw new BadHttpRequestException(message, exception);             }              if (_rdgLogger != null)             {                 _invalidJsonRequestBody(_rdgLogger, parameterTypeName, parameterName, exception);             }         }          private static readonly Action<ILogger, string, string, Exception?> _invalidJsonRequestBody =             LoggerMessage.Define<string, string>(LogLevel.Debug, new EventId(2, "InvalidJsonRequestBody"), "Failed to read parameter \"{ParameterType} {ParameterName}\" from the request body as JSON.");          public void ParameterBindingFailed(string parameterTypeName, string parameterName, string sourceValue)         {             if (_shouldThrow)             {                 var message = string.Format(CultureInfo.InvariantCulture, "Failed to bind parameter \"{0} {1}\" from \"{2}\".", parameterTypeName, parameterName, sourceValue);                 throw new BadHttpRequestException(message);             }              if (_rdgLogger != null)             {                 _parameterBindingFailed(_rdgLogger, parameterTypeName, parameterName, sourceValue, null);             }         }          private static readonly Action<ILogger, string, string, string, Exception?> _parameterBindingFailed =             LoggerMessage.Define<string, string, string>(LogLevel.Debug, new EventId(3, "ParameterBindingFailed"), "Failed to bind parameter \"{ParameterType} {ParameterName}\" from \"{SourceValue}\".");          public void RequiredParameterNotProvided(string parameterTypeName, string parameterName, string source)         {             if (_shouldThrow)             {                 var message = string.Format(CultureInfo.InvariantCulture, "Required parameter \"{0} {1}\" was not provided from {2}.", parameterTypeName, parameterName, source);                 throw new BadHttpRequestException(message);             }              if (_rdgLogger != null)             {                 _requiredParameterNotProvided(_rdgLogger, parameterTypeName, parameterName, source, null);             }         }          private static readonly Action<ILogger, string, string, string, Exception?> _requiredParameterNotProvided =             LoggerMessage.Define<string, string, string>(LogLevel.Debug, new EventId(4, "RequiredParameterNotProvided"), "Required parameter \"{ParameterType} {ParameterName}\" was not provided from {Source}.");          public void ImplicitBodyNotProvided(string parameterName)         {             if (_shouldThrow)             {                 var message = string.Format(CultureInfo.InvariantCulture, "Implicit body inferred for parameter \"{0}\" but no body was provided. Did you mean to use a Service instead?", parameterName);                 throw new BadHttpRequestException(message);             }              if (_rdgLogger != null)             {                 _implicitBodyNotProvided(_rdgLogger, parameterName, null);             }         }          private static readonly Action<ILogger, string, Exception?> _implicitBodyNotProvided =             LoggerMessage.Define<string>(LogLevel.Debug, new EventId(5, "ImplicitBodyNotProvided"), "Implicit body inferred for parameter \"{ParameterName}\" but no body was provided. Did you mean to use a Service instead?");          public void UnexpectedJsonContentType(string? contentType)         {             if (_shouldThrow)             {                 var message = string.Format(CultureInfo.InvariantCulture, "Expected a supported JSON media type but got \"{0}\".", contentType);                 throw new BadHttpRequestException(message, StatusCodes.Status415UnsupportedMediaType);             }              if (_rdgLogger != null)             {                 _unexpectedJsonContentType(_rdgLogger, contentType ?? "(none)", null);             }         }          private static readonly Action<ILogger, string, Exception?> _unexpectedJsonContentType =             LoggerMessage.Define<string>(LogLevel.Debug, new EventId(6, "UnexpectedContentType"), "Expected a supported JSON media type but got \"{ContentType}\".");          public void UnexpectedNonFormContentType(string? contentType)         {             if (_shouldThrow)             {                 var message = string.Format(CultureInfo.InvariantCulture, "Expected a supported form media type but got \"{0}\".", contentType);                 throw new BadHttpRequestException(message, StatusCodes.Status415UnsupportedMediaType);             }              if (_rdgLogger != null)             {                 _unexpectedNonFormContentType(_rdgLogger, contentType ?? "(none)", null);             }         }          private static readonly Action<ILogger, string, Exception?> _unexpectedNonFormContentType =             LoggerMessage.Define<string>(LogLevel.Debug, new EventId(7, "UnexpectedNonFormContentType"), "Expected a supported form media type but got \"{ContentType}\".");          public void InvalidFormRequestBody(string parameterTypeName, string parameterName, Exception exception)         {             if (_shouldThrow)             {                 var message = string.Format(CultureInfo.InvariantCulture, "Failed to read parameter \"{0} {1}\" from the request body as form.", parameterTypeName, parameterName);                 throw new BadHttpRequestException(message, exception);             }              if (_rdgLogger != null)             {                 _invalidFormRequestBody(_rdgLogger, parameterTypeName, parameterName, exception);             }         }          private static readonly Action<ILogger, string, string, Exception?> _invalidFormRequestBody =             LoggerMessage.Define<string, string>(LogLevel.Debug, new EventId(8, "InvalidFormRequestBody"), "Failed to read parameter \"{ParameterType} {ParameterName}\" from the request body as form.");     } } 

Code and pdf at https://ignatandrei.github.io/RSCG_Examples/v2/docs/RDG