[WASM] Better double (F64) support in MonoPlatform.ts

[GeroL]

Is there an existing issue for this?

• I have searched the existing issues

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

I am sending many double arrays per Unmarshalled invokes to my JS functions
I saw the Blazor.platform.toUint8Array function but it seems that this is the only helper function so far

Describe the solution you'd like

It could be new APIs like toFloat(32/64)Array like here
Also some helper functions could be implemented like the ones for float (F32)

Additional context

The types for F64 support are implemented here https:/dotnet/aspnetcore/blob/main/src/Components/Web.JS/@types/dotnet/dotnet.d.ts

I have now a function in javascript like this:

function toFloat64Array(array){
    const dataPtr = Blazor.platform.getArrayDataPointer(array);
    const length = Blazor.platform.getValueI32(dataPtr);
    const f64Array = new Float64Array(length);
    f64Array.set(Module.HEAPF64.subarray(dataPtr + 4, dataPtr + 4 + length));
    return f64Array;
}

I wasn't able to test it due to lack of time.

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Issue Details

---

Is there an existing issue for this?

• I have searched the existing issues

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

I am sending many double arrays per Unmarshalled invokes to my JS functions
I saw the Blazor.platform.toUint8Array function but it seems that this is the only helper function so far

Describe the solution you'd like

It could be new APIs like toFloat(32/64)Array like here
Also some helper functions could be implemented like the ones for float (F32)

Additional context

The types for F64 support are implemented here https:/dotnet/aspnetcore/blob/main/src/Components/Web.JS/@types/dotnet/dotnet.d.ts

I have now a function in javascript like this:

function toFloat64Array(array){
    const dataPtr = Blazor.platform.getArrayDataPointer(array);
    const length = Blazor.platform.getValueI32(dataPtr);
    const f64Array = new Float64Array(length);
    f64Array.set(Module.HEAPF64.subarray(dataPtr + 4, dataPtr + 4 + length));
    return f64Array;
}

I wasn't able to test it due to lack of time.

Author:	GeroL
Assignees:	pavelsavara
Labels:	arch-wasm, area-VM-meta-mono
Milestone:	-