Use View Components, not Partial Views, in ASP.NET Core

Why use View Components and not Partial Views? The biggest reason is that when inserting a Partial View into a Razor page, all the ViewData associated with the calling View is automatically associated with the Partial View. This means that a Partial View may behave very differently on one Razor page than on another. With View Components, you control what gets shared to your View Components.

[sulmarpl]

Excellent explanation. Thanks to that I decided to buy Peter's course about ASP.NET Core Tag Helpers and View Components on Pluralsight. I recommend.

[ssirois]

Thanks Peter! I was looking around for a simple explanation of view component in Razor and YT land this in my search... lucky me 🙂

[Tolg]

Excellent video and very helpful. It's fantastic that it has an accompanying blog + git repository. Well done, thank you!

[ganjalaw]

This works great! I agree it is nicely self-contained and easy to work with. Thank you!

[DavidHouseGA]

Thanks for this video, very succinct!

[HA-fqxc]

Nice explanation
Thanks and
Greeting from the desert

[spauldingcanada]

AARGH!!! I have been driving myself crazy! I am new to Razor Pages and am migrating a large application that extensively used nested ascx pages where a nested page would call a second nested page while passing objects forward. I can see no way of getting OnGet() on a nested view or Razor Page to be called, nor can I pass a variable or even call a child method from a parent method. Please can you spread some light on this?

[szafar]

how can you refresh a view component using javascript

[chadgregory]

This makes no damn sense if you still have to use js.... whats the difference between using an ajax request and hitting a controller and using a partial view and then injecting the returned html into the proper dom element?

can I somehow create a component thats for example, something like
<vc:list-notes notes-on-page=variable>
</vc:list-notes>

and on that page when i change the value of variable, it hits the view component and loads what it needs to that way... or does this still require js?

[weBeatMedicare]

So, ViewComponent is killer because encapsulation and no side effects...
If that's supposed to be convincing, then what's an example of a side effect in a partial view?

[STUPIDYOUTUBE_HIDINGMSGS]

Other than being 'invoked' automatically, this video doesn't explain fully why a partial view cannot be used in place of another one of those MS additional-useless-feature called ViewComponent. If Microsoft developed what they think now is a useless partial view, now they're using another soon-to-be useless ViewComponent.

[hqcart]

Why not use BLAZOR ??? it does exactly this with much ease!

[NBGTFO]

Using View Components everywhere is overkill and completely unnecessary. They each have their correct situational usage. Using either one everywhere is just wrong.