Simpler way to declare two-way bound parameters in Blazor components

[lindespang]

Is your feature request related to a problem? Please describe.

I find myself writing a lot of boilerplate code when doing two-way bindings in Blazor like below. (It adds up if you have multiple parameters..)

@code {
    [Parameter]
    public TValue Value { get; set; }

    [Parameter]
    public EventCallback<TValue> ValueChanged { get; set; }
}

I think it would be nice to introduce another attribute that would generate the same source by only declaring one property.

Describe the solution you'd like

I would like it to look something like below (attribute semantics up for discussion)

@code {
    [BindableParameter]
    public TValue Value { get; set; }
}

Which would generate exactly the same source as

@code {
    [Parameter]
    public TValue Value { get; set; }

    [Parameter]
    public EventCallback<TValue> ValueChanged { get; set; }
}

Additional context

If I haven't missed anything obvious here I think this is a very clean and non-intrusive solution. I always write my bindable properties like this and have not yet encountered any situation that breaks that rule. Therefor I think this added attribute makes sense.

Please give feedback on this and let me know if I should take a look at it or if you want to do it yourselves!

[mkArtakMSFT]

Thanks for contacting us.
We plan to implement source generators for Razor in .NET 6. Once that work is done, you'll be able to implement your own source generator which would do what you want.