H3D-Zoo/AOP.Fody

Usage

NuGet installation

PM> Install-Package Fody

The Install-Package Fody is required since NuGet always defaults to the oldest, and most buggy, version of any dependency.

Add to FodyWeavers.xml

Add <BasicFodyAddin/> to FodyWeavers.xml

<?xml version="1.0" encoding="utf-8" ?>
<Weavers>
  <AOP/>
</Weavers>

AOP.Fody Project

A AspectInjector project wrapper by code rewrite for Fody Support. Aspect Injector is a framework for creating and injecting aspects into your .net assemblies.

Features

Compile-time injection
No runtime dependencies
Advice debugging
Interface injection
Injection into Methods, Properties, Events
Ability to wrap method around

Concept

Aspect is a class which contains a set of advices - methods which should be injected to certain points in the code. Each advice has mandatory attributes which define a kind of target class members (constructor, getter, setter, regular method etc.) and join points - points in the code where this advice should be injected (before target member, after or both). Aspects and advices are marked with appropriate attributes. For example, we have a class with one method marked as advice:

[Aspect(Aspect.Scope.Instance)]
class TraceAspect
{
	private int count;
	
	[Advice(Advice.Type.Before, Advice.Target.Method)]
	public void CallCountTrace()
	{
		Console.WriteLine("Call #{0}", count);
		count++;
	}
}

Having it we can apply this aspect to any method:

//Method CallCountTrace of TraceAspect instance will be called at the beginning of Calculate() 
[Inject(typeof(TraceAspect))]
public void Calculate() { }

... or a set of methods of some class:

//Method CallCountTrace of TraceAspect instance will be called at the beginning of Load() and Save()
[Inject(typeof(TraceAspect))]
class Container
{
    public string Name { get; set; }

    public void Load() { }
    public void Save() { }
}

... but not to properties in this case:

//Will not work - CallCountTrace() advice is applicable to regular methods only
[Inject(typeof(TraceAspect))]
public string Name { get; set; }

Please note that there will be only one instace of an aspect per target class regardless of number of affected members. So in the example above Container class will have only one instance of TraceAspect, so both Load() and Save() will increment the same call counter.

Target Frameworks

This project must target and netstandard2.1 (for .NET Framework net46 or above) so that it can target msbuild.exe or dotnet build.

H3D-Zoo / AOP.Fody