Templated generic blazor component does not accept template context RenderFragment<T> for different type T

[awajan]

When you try to compose and consume a generic (typed) blazor component and expose a RanderFragment parameter, T is being restricted to be the same generic type of the component. Otherwise, the consuming component would show the below error when placing the template markup.

Example: <Component1> is a typed component with type T1, exposing a parameter named Header for example, that is RenderFragmanet<T2>

Now, in Component2 if you try to consume Component1 as below:

<Component1>
  <Header></Header>
</Component1>

The below error would show:

The type or namespace 'T2' does not exist in the namespace '__Blazor....'.

Thanks

[javiercn]

@awajan thanks for contacting us.

I've updated your post for clarity. I believe that if you want to have a different RenderFragment you would need to declare your templated component to have more than one type parameter (like <T1,T2>, which I'm not 100% sure is possible, but I believe so).

That should allow you to expose RenderFragment<T> with a different type.

Di we understood everything correctly?

[awajan]

I think you got me correctly, but there is no where mentioned in the documentation that RenderFragment should have T matching the typed component parameter. In addition to that, I was able to specify RenderFragment where T can be any type for components that are not typed (non-generic).

[javiercn]

In addition to that, I was able to specify RenderFragment where T can be any type for components that are not typed

I'm assuming that you mean you were able to declare something like RenderFragment<Animal> that's totally valid and expected, Razor components are compiled to C# classes so the same rules apply to them.

You can't declare a non generic class with a generic property in it and in the same way you can't have a RenderFragment property where T is not a parameter defined with typeparam

[awajan]

this is not completely true:

"You can't declare a non generic class with a generic property in it and in the same way you can't have a RenderFragment property where T is not a parameter defined with typeparam"

I used RenderFragment on non generic components, and this was completely fine. The issue remains as stated initially and it is a bug.

[javiercn]

@awajan could you provide a minimal repro project that illustrates the issue?

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