I am working on a server side application which should dynamically load modules at startup based on whether or not they exist as assemblies. I've done something similar before, but this time it's production code and I want to use frameworks for modularization and instantization (using IoC containers). I initially found Microsoft's Prism (with Unity) to be a suitable framework to do this, but I am growing concerned as I am implementing initialization and bootstrapping. The server will not have it's own GUI and will presumably run as a windows service at a later time. (I'm developing it as a simple console application in the meantime.) Various clients (roughly one client application per module) will be developed to interact with the server over WCF.
Should I even be using Prism for such an application, since it seems so geared towards GUI-enabled applications? I stopped coding when using the base class Microsoft.Practices.Prism.UnityExtensions.UnityBootstrapper which requires implementation of a CreateShell() method. I kind of expected it to be named something like Run() or something similar. I don't really have a shell, or at least a GUI shell. Am I reading to much into this, and does it make sense to use Prism without worrying about it having potentially redundant GUI functionality? Am I using the right tool for the job?
I think you already know the answer. Prism is for client applications. Even if you get this working in your server environment, there will be a lot of the framework that's just in the way. You do want to use an IoC container and you're already using Unity for this (Prism by default uses Unity). My advice, ditch Prism and start wiring everyting using Unity. Dynamically loading assemblies is super easy. You don't need a bloated framework just for loading assemblies.
As stated in Steven's answer, Prism is intended for client applications. Unity is a good choice of dependency injection container, however I believe for your situation you would likely be much better off making use of either the Managed Extensibility Framework (MEF) or the Managed Addin framework (MAF).
Unity is primarily is used when the type mappings are known at compile time, before version 2.1, there was no out of the box support for dynamic type registrations.
The Managed Extensibility Framework is ideal at dynamically discovering types for dependency injection. See here for the amount of options it provides for dynamically loading types from runtime assemblies.
The Managed Addin Framework is a part of the .NET framework since .NET 3.5, one of it's largest features is the assembly isolation, assemblies can be loaded into separate app domains and even processes and then still be used. This is great for third party addins, if they are buggy and crash, they will not bring your application down with them.
from last couple of days I was reading about the PRISM, CAL & MEF. All of these support the composition, modularity, bootstrapers, shell and region etc.
So question comes in my mind is. Where these all support main features for modularity so which framework to use and where they fit best.
can somebody guide me for the comparing these techs?
CAL was an old name for PRISM that is no longer in use. PRISM uses MEF, Unity or any other inversion of control library to implement composition and dependency injection. MEF is newer and easier to work with than Unity, but it all depends on the templates you decide to use.
Perhaps you should check the Developer's Guid to Prism for a better understanding of PRISM. PRISM's use of IoC/DI is described in Modular Application Development/Dependency Injection and Modular Applications
You should also note that PRISM is considered over-engineered, even if you think your application fits the Composite Application definition (it probably doesn't).
It is much easier to get up to speed with MVVM and WPF development if you use a simpler framework like Caliburn.Micro or MVVM Light.
CAL is a former name of Prism framework. MEF is a IoC container (one of them). Prism can use different IoC containers (Unity and MEF out of the box).
So, your question doesn't makes any sense.
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Which .NET Dependency Injection frameworks are worth looking into?
Hi,
As a new kid in the C#/.NET block just moved in from Java neighbourhood, I am looking for options in Dependency Injection/IoC frameworks for .NET/C#.
From Scott Hanselman's blog post few years ago I got a fairly long list of DI frameworks, but there was really not enough information to go with beyond the list itself (plus a license and a version number) to make any semi-intelligent choice. Nor have I developed a ghestalt of the relative popularity (and thus the community support available) for any of these. And the list itself dates from 2008, which makes it a bit outdated, so I would like to ask kindly SO community for help on this matter.
Please list (or vote for) your favourite DI framework, adding a link to framework official website and please be so kind as to provide some reasoning for helping me and others developers like me to make a choice.
A code sample snippets for declaring and injecting dependencies would be of great help as well.
NB: Please restrict yourselves to one entry per response please, to keep it simple and objective.
I have used Ninject before and got on well with it. There are code samples on the front page of the website.
http://ninject.org/
Edit:
Ninject also supports MVC
Of those I have tried, I like Unity best by far. Easy to use, and feature rich. A note is that it's not supported if you are developing for Windows Phone 7.
Of the list I've tried Unity, StructureMap and Autofac.
I perfer StructureMap, I think it's the most straightforward and easiest to use. (didn't spend much time with Autofac tho since was just messing in my own time)
You could also use MEF, but be aware that MEF is not only for this purpose. Mostly MEF is a little oversized for normal DI scenarios, but very usefull if you intent to develop a extendible app.
My application should be extensible. For my own needs I have implement some services. These services are based on the IoC/DI princple. So the services encapsulate the concept of the application.
For exsample, there are an IApplicationService. The ApplicationService exposes information about the current exceuting application. There are specified the AssemblyInfo and so forth. An other exsample is the INavigationService(see mef.codeplexcom in the samples). This services provides some properties where are information about the current selected item specified and also some events.
I think, that the "service approach" is the easiest and simplifies the extension points for the application. So, I am not sure that this is really the best approach. What do you think? How do you would implement "extensions points" in an application like addins/addons/plugins ... ?
Thanks in advance for your replies! And sorry, my english is poor. ;)
Are you familiar with MEF (Managed Extensibility Framework)?
The Managed Extensibility Framework (or MEF for short) simplifies the creation of extensible applications. MEF offers discovery and composition capabilities that you can leverage to load application extensions.
You seriously need to look at MEF - the Managed Extensibility Framework.
Managed Extensibility Framework Overview
Building Composable Apps in .NET 4 with the Managed Extensibility Framework
MEF on Codeplex
It's a great new framework that Microsoft itself is using in e.g. Visual Studio 2010 for its extensibility story. Great and easy to use - why reinvent the wheel when you can use something that thousands of dev will use shortly??
Yes, I am familiar with MEF. I also use the concept of MEF, but there some disadvantages. My application is IoC/DI like and together with MEF is a bit complicated. MEF is not really a DI container so to use MEF with an other DI container(e.g. ninject, unity, ...) is difficult to implment this. I won't to use MEF with other DI containers. So to mix MEF with other DI containers is not really good.
I hope you can understand my concern.
Addition: It is not possible to load extensions in to an AppDomain in MEF. So this is for my needs not good. System.AddIn or MAF supports this, but I won't use System.AddIn, because this is very heavy ... .
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Closed 10 years ago.
Which C#/.NET Dependency Injection frameworks are worth looking into?
And what can you say about their complexity and speed.
edit (not by the author): There is a comprehensive list of IoC frameworks available at https://github.com/quozd/awesome-dotnet/blob/master/README.md#ioc:
Castle Windsor - Castle Windsor is best of breed, mature Inversion of Control container available for .NET and Silverlight
Unity - Lightweight extensible dependency injection container with support for constructor, property, and method call injection
Autofac - An addictive .NET IoC container
DryIoc - Simple, fast all fully featured IoC container.
Ninject - The ninja of .NET dependency injectors
Spring.Net - Spring.NET is an open source application framework that makes building enterprise .NET applications easier
Lamar - A fast IoC container heavily optimized for usage within ASP.NET Core and other .NET server side applications.
LightInject - A ultra lightweight IoC container
Simple Injector - Simple Injector is an easy-to-use Dependency Injection (DI) library for .NET 4+ that supports Silverlight 4+, Windows Phone 8, Windows 8 including Universal apps and Mono.
Microsoft.Extensions.DependencyInjection - The default IoC container for ASP.NET Core applications.
Scrutor - Assembly scanning extensions for Microsoft.Extensions.DependencyInjection.
VS MEF - Managed Extensibility Framework (MEF) implementation used by Visual Studio.
TinyIoC - An easy to use, hassle free, Inversion of Control Container for small projects, libraries and beginners alike.
Stashbox - A lightweight, fast and portable dependency injection framework for .NET based solutions.
Original answer follows.
I suppose I might be being a bit picky here but it's important to note that DI (Dependency Injection) is a programming pattern and is facilitated by, but does not require, an IoC (Inversion of Control) framework. IoC frameworks just make DI much easier and they provide a host of other benefits over and above DI.
That being said, I'm sure that's what you were asking. About IoC Frameworks; I used to use Spring.Net and CastleWindsor a lot, but the real pain in the behind was all that pesky XML config you had to write! They're pretty much all moving this way now, so I have been using StructureMap for the last year or so, and since it has moved to a fluent config using strongly typed generics and a registry, my pain barrier in using IoC has dropped to below zero! I get an absolute kick out of knowing now that my IoC config is checked at compile-time (for the most part) and I have had nothing but joy with StructureMap and its speed. I won't say that the others were slow at runtime, but they were more difficult for me to setup and frustration often won the day.
Update
I've been using Ninject on my latest project and it has been an absolute pleasure to use. Words fail me a bit here, but (as we say in the UK) this framework is 'the Dogs'. I would highly recommend it for any green fields projects where you want to be up and running quickly. I got all I needed from a fantastic set of Ninject screencasts by Justin Etheredge. I can't see that retro-fitting Ninject into existing code being a problem at all, but then the same could be said of StructureMap in my experience. It'll be a tough choice going forward between those two, but I'd rather have competition than stagnation and there's a decent amount of healthy competition out there.
Other IoC screencasts can also be found here on Dimecasts.
It depends on what you are looking for, as they each have their pros and cons.
Spring.NET is the most mature as it comes out of Spring from the Java world. Spring has a very rich set of framework libraries that extend it to support Web, Windows, etc.
Castle Windsor is one of the most widely used in the .NET platform and has the largest ecosystem, is highly configurable / extensible, has custom lifetime management, AOP support, has inherent NHibernate support and is an all around awesome container. Windsor is part of an entire stack which includes Monorail, Active Record, etc. NHibernate itself builds on top of Windsor.
Structure Map has very rich and fine grained configuration through an internal DSL.
Autofac is an IoC container of the new age with all of it's inherent functional programming support. It also takes a different approach on managing lifetime than the others. Autofac is still very new, but it pushes the bar on what is possible with IoC.
Ninject I have heard is more bare bones with a less is more approach (heard not experienced).
The biggest discriminator of Unity is: it's from and supported by Microsoft (p&p). Unity has very good performance, and great documentation. It is also highly configurable. It doesn't have all the bells and whistles of say Castle / Structure Map.
So in summary, it really depends on what is important to you. I would agree with others on going and evaluating and seeing which one fits. The nice thing is you have a nice selection of donuts rather than just having to have a jelly one.
Autofac. https://github.com/autofac/Autofac It is really fast and pretty good. Here is a link with comparisons (made after Ninject fixed a memory leak issue).
http://www.codinginstinct.com/2008/05/ioc-container-benchmark-rerevisted.html
Ninject is great. It seems really fast, but I haven't done any comparisons. I know Nate, the author, did some comparisons between Ninject and other DI frameworks and is looking for more ways to improve the speed of Ninject.
I've heard lots of people I respect say good things about StructureMap and CastleWindsor. Those, in my mind, are the big three to look at right now.
I use Simple Injector:
Simple Injector is an easy, flexible and fast dependency injection library that uses best practice to guide your solutions toward the pit of success.
I'm a huge fan of Castle. I love the facilities it also provides beyond the IoC Container story. It really simplfies using NHibernate, logging, AOP, etc. I also use Binsor for configuration with Boo and have really fallen in love with Boo as a language because of it.
I spent the better part of a day struggling without success to get the simplest Spring.NET example working. Could never figure out how to get it to find my assembly from the XML file. In about 2 hours, on the other hand, I was able to get Ninject working, including testing integration with both NUnit and MSTest.
I've used Spring.NET in the past and had great success with it. I never noticed any substantial overhead with it, though the project we used it on was fairly heavy on its own. It only took a little time reading through the documentation to get it set up.
I can recommend Ninject. It's incredibly fast and easy to use but only if you don't need XML configuration, else you should use Windsor.
The great thing about C# is that it is following a path beaten by years of Java developers before it. So, my advice, generally speaking when looking for tools of this nature, is to look for the solid Java answer and see if there exists a .NET adaptation yet.
So when it comes to DI (and there are so many options out there, this really is a matter of taste) is Spring.NET. Additionally, it's always wise to research the people behind projects. I have no issue suggesting SourceGear products for source control (outside of using them) because I have respect for Eric Sink. I have seen Mark Pollack speak and what can I say, the guy just gets it.
In the end, there are a lot of DI frameworks and your best bet is to do some sample projects with a few of them and make an educated choice.
Good luck!
I think a good place to start is with Ninject, it is new and has taken into account alot of fine tuning and is really fast. Nate, the developer, really has a great site and great support.
Spring.Net is quite solid, but the documentation took some time to wade through. Autofac is good, and while .Net 2.0 is supported, you need VS 2008 to compile it, or else use the command line to build your app.