Trying to create a Dependency Injection/IoC Container FROM SCRATCH

[@ikroeber]

This was really awesome to watch. About the actual performance of instantiating via the Activator, you can also register the implementation via expressions to make it run faster.

[@kxpes]

I really love the approach, if we had to, this is exacly way we would had to do dependency injection at university. To understand this, but it is beautiful to see functionality made from scratch to more or less see what internals are doing.

[@kopilkaiser8991]

It was a bit complicated to keep up. Your modules which you discuss are high level and the reason it gets difficult to understand is because you try to explain the skeleton behind each code which is difficult to understand. It is easier to learn how to use a tool than learning in making the tool 😅 but I never give up in trying to make myself understand. Thank you for your hard work and efforts ❤

[@psycho.2u]

The best video I've ever seen about dependency injection so far

[@KillerPhantom123]

Great tutorial, love the new format!, thanks for everything Nick

[@daoquanganh8aanh81]

great tutorial for me to understand how to implement DI, thank u 🎉

[@niluniverse]

You are Oracle of Technology! You are making programming fun, and ridiculously easy.

[@standiallo]

This man is fit for I.O.C. !

[@JagadishNallamilli]

This is just Perfect!!

[@faisletoismeme]

Wow, you are awesome. A great demonstration of your mastery. I am impressed.

[@nishad3445]

Amazing run through of an unfamiliar problem for me. Keep up the awesome content!

[@CrapE_DM]

So much of that logic should be kept in the ServiceDescriptor (with different subtypes to get rid of a lot of the ifs). That and a little bit more cleaning, and this would be perfectly fine. Since you did this live while seeming to make sure you stay at a decent pace, this is pretty good work.

[@CrapE_DM]

But, personally, I hate using reflection to instantiate stuff. So, instead of registering implementation types, I would pass in functions to call. It's a bit more manual on the part of the app creator, but it removes some runtime errors and moves them to compile time.

[@alihsanelmas]

Nice demonstration!

[@shuvo9131]

Thanks Nick. This tutorial is very informative and waiting to see more.

[@m.kozylov]

Thanks! It would be interesting to see implementation of the scoped service provider.

[@RahulSingh-il1xk]

Hi Nick, This is your new fan 😊. I had one observation, don't you think we need to modify Line 26 of GetService() for transient services when the user provides the implementation. Currently, it returns the same implementation (singleton) instead of instantiating a new one.

[@arashmalek5224]

good job. by this tutorial, I understand the concept of dependency injection very well.

[@Radictor44]

I love your curiosity

[@sezif3157]

this video is gold bro , ty :)

[@bsgamer5069]

I want to buy your Dependency injection course. Does it explain about the reflection part ?

[@turkodeco]

Hey, which keyboard are you using?

[@martinprohn2433]

Is it really good practive to throw a literal "Exception"? I doubt that: Because than the exception can only be caught with "catch(Exception)" which itself is already a code smell. Why not use "KeyNotFoundException", wouldn't that be the more appropriate exception type here?

[@nickchapsas]

Sure

[@Anubis10110]

Awesome stuff

[@armanx2]

I was wondering what if you would write extension method for Object and call it from anywhere in class to get your Dependencies and get your dependency without using activator would not that be more performant ? I have never seen any Dependency injector doing it but the idea i wonder if that would work. I will try out once I have time :)

[@mofolom]

it would have been nice to build this using unit tests. looking at what you want, then verifying it. this looks like you know what you want to do. don't trust the debugger, write the tests.

[@vbaclasses3553]

I would love to see this done TDD as well.

[@xHaplo]

Hey @Nick Chapsas, amazing videos! Did you ever get around to writing the Scoped implementation? would really like to see your, well, implementation for it :)

[@marsen_lin]

How did you do it so fast? 2:02 Copy the to other lines?

[@11r3start11]

in visual studio and many other editors its Crtl + D

[@jckprobability5204]

I love you Nick...

[@svenheidemann3834]

Made this one in python, really funny :D

[@stebberg]

Very cool

[@adoulou340]

Great video, could we register 2 classes which implement the same interface ? Thanks

[@paulkoopmans4620]

In Nick's example you could have registered a second one... but you would never be able to get it because it in the GetService method he looks it up by SingleOrDefault which would then throw an exception. If he would have used an dictionary as he commented then you could not a second registration. Now... there are dependency frameworks that can do that... castle is one that I know... but then your service registrations would have to come with extra qualifiers so that you can "find" the right one. Something like: RegisterTransient(AccountType.Debit); RegisterTransient(AccountType.Savings); Then a GetService or Resolve could be: GetService(AccountType.Savings);

[@adoulou340]

@@paulkoopmans4620 Thanks Paul

[@meditationheathandwellness781]

Excellent

[@my3m]

Quality content

[@kieferFernandez]

Awesome!!

[@Cognitoman]

Hmm I’d like to create one for my vanilla JavaScript project as well

[@maximusatenko4128]

cool!

[@Cognitoman]

What’s up homie ?

[@hokoder7371]

if you dont mind, can you expand this tutorial with the di and ioc of asp.net core template project? i came across this tutorial when i was looking for something to understand their architecture. this tutorial is good but i could find similar or same examples from stackoverflow and codeprojct and i feel 30mins video is pretty long. cheers.

[@mariomorazan9473]

The fun part is when the constructors are Not parameterless XD

[@nickchapsas]

The video covers it with dynamic resolution

[@SAXXSSX]

Hey nick, can u make asp.net core webapi microservices playlist?

[@nickchapsas]

I definitely wanna explore micro-services but on a more architectural level rather then implementation. A microservice is really a service that does one thing. This wouldn't be demonstrated properly in an asp.net core playlist since microservices can be from many different technologies and they usually are.

[@vr4306]

Nick Chapsas waiting for this