Support passing float[] (Single[]) to JS from .NET via [JSImport]

[Matheos96]

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

I recently tried (and failed) to pass a simple float[] from .NET to JS. This is obviously not supported, as per the docs:

I got it working by casting my floats to doubles using Linq, quite an ugly way which probably could do in a better way:
var myDoubles = myFloats.Select(f => (double)f).ToArray();
passing this to JS works.

Describe the solution you'd like

It struck me, if the "workaround" is this simple, why could it not be indirectly supported by the [JSImport] API itself? Either through casting floats to doubles or something more clever? I mean, whatever we can fit in a float, could most definately fit in a double. If you want to explicit then force us to use [JSMarshalAs<JSType.Array<JSType.Number>>] or something to make it work.

Thoughts?

Additional context

No response

[ghost]

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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 recently tried (and failed) to pass a simple float[] from .NET to JS. This is obviously not supported, as per the docs:

I got it working by casting my floats to doubles using Linq, quite an ugly way which probably could do in a better way:
var myDoubles = myFloats.Select(f => (double)f).ToArray();
passing this to JS works.

Describe the solution you'd like

It struck me, if the "workaround" is this simple, why could it not be indirectly supported by the [JSImport] API itself? Either through casting floats to doubles or something more clever? I mean, whatever we can fit in a float, could most definately fit in a double. If you want to explicit then force us to use [JSMarshalAs<JSType.Array<JSType.Number>>] or something to make it work.

Thoughts?

Additional context

No response

Author:	Matheos96
Assignees:	-
Labels:	arch-wasm, untriaged, area-System.Runtime.InteropServices.JavaScript, os-browser
Milestone:	-

[maraf]

cc @pavelsavara

[pavelsavara]

It struck me, if the "workaround" is this simple, why could it not be indirectly supported by the [JSImport] API itself?

Indeed, there is duplicate feature request for that. #97380

Thoughts?

I found few ways how you can do it here https://stackoverflow.com/questions/69805135/how-does-c-sharp-convert-double-arrays-to-float-arrays-or-int-arrays

I guess float[] floatValues = Array.ConvertAll(values, Convert.ToSingle); would be fastest.

[Matheos96]

It struck me, if the "workaround" is this simple, why could it not be indirectly supported by the [JSImport] API itself?

Indeed, there is duplicate feature request for that. #97380

Thoughts?

I found few ways how you can do it here https://stackoverflow.com/questions/69805135/how-does-c-sharp-convert-double-arrays-to-float-arrays-or-int-arrays

I guess float[] floatValues = Array.ConvertAll(values, Convert.ToSingle); would be fastest.

Ok. Thanks, sounds good. I guess your example in my case would be something like
double[] doubleValues = Array.ConvertAll(floatValues, Convert.ToDouble);
as my values are float but they need to be double for it to work, as it is today.