Can Blazor JavaScript return an array?

Question

I'm trying to get some html element position in javascript and passe it back to the C# but i get that error : Serialization and deserialization of 'System.Type' instances are not supported.

Blazor:

double[] jsResult =  await _jsRuntime.InvokeAsync<double[]>("getBottomOffset", _element);
double bottomOffset = jsResult[0];
double height = jsResult[1];
_resultsStyle = Options.Count * ResultHeight < bottomOffset ? $"top: 0; left: 0; " : $"bottom: -{height}px; left: 0;";

JS :

function getBottomOffset(el) {
const rect = el.getBoundingClientRect();
return [(window.innerHeight - rect.bottom), rect.height];

}

Answer 1

Try using this

public class data
    {
        public double bottomOffset { get; set; } 
        public double height { get; set; } 
    }

Calling javascript function

data obj = await _jsRuntime.InvokeAsync<data>("getBottomOffset", _element);

your javascript function

function getBottomOffset(el) {
    const rect = el.getBoundingClientRect();
    
    return { bottomOffset: (window.innerHeight - rect.bottom), height: rect.height };
}