Improve multiple-level binding section introduction

[guardrex]

Description

Improve per the discussion 👉 dotnet/aspnetcore#57962

Basically, we want a better description on why :get/:set binding is in use today (7.0 or later) in the approach described for multiple-level binding across components. It was ... AFAIK ... to avoid having to use a third (dummy) property with a setter to invoke the event callback. It simplifies things. However, the introduction really doesn't explain that out, and it probably should.

We also want to see how Artak's description should be worked into the coverage ...

with the @bind-{parameter}:set you can react to the change before it happens, and yes, change the applied value if necessary before it gets applied. Whereas with the change event registration you get the notification after the change was applied.

... which might mean some added or different content at ...

https://learn.microsoft.com/en-us/aspnet/core/blazor/components/data-binding?view=aspnetcore-9.0#use-bindgetbindset-modifiers-and-avoid-event-handlers-for-two-way-data-binding

Page URL

https://learn.microsoft.com/en-us/aspnet/core/blazor/components/data-binding?view=aspnetcore-8.0

Content source URL

https://github.com/dotnet/AspNetCore.Docs/blob/main/aspnetcore/blazor/components/data-binding.md

Document ID

3f912dfc-5ba5-6c6c-ba93-1ae78508a5cc

Article author

@guardrex