Why is createJSObjectReference not usable for functions?

[trungnt2910]

createJSObjectReference, the function that powers IJSRuntime and IJSObjectReference, has this line:

aspnetcore/src/JSInterop/Microsoft.JSInterop.JS/src/src/Microsoft.JSInterop.ts

Line 148 in 7033ec7

if (jsObject && typeof jsObject === "object") {

This means things like this will fail:

        await using var func = await JSRuntime.InvokeAsync<IJSObjectReference>("window.alert");
        await func.InvokeVoidAsync("call", "Hello World!");

Why is that check there in the first place? Without such restrictions, issues like #31151 are basically solved.

[oroztocil]

This has been implemented in #61453 which relaxes the condition to:

if (jsObject && (typeof jsObject === "object" || jsObject instanceof Function)) { ... }

[trungnt2910]

Interesting to see this actually getting read by the team. Thanks!

Now we can access most JavaScript runtime functionality from JSRuntime without requiring any actual helper JS code:
https://trungnt2910.com/blazor-goodbye-js#attempt---reflectconstruct

@inject IJSRuntime JSRuntime

<button @onclick="Button_Click">Click me</button>

@code {
    private async Task Button_Click()
    {
        await using var ctor = await JSRuntime.InvokeAsync<IJSObjectReference>("Set.bind");
        await using var set = await JSRuntime.InvokeAsync<IJSObjectReference>("Reflect.construct",
            new object?[] { ctor, new string[] { "lxmonika" } });
        await JSRuntime.InvokeVoidAsync("console.log", set);
    }

}

[trungnt2910]

Actually just saw the new InvokeNewAsync API, which makes my trick obsolete 😅