CaritasPWA/Shared/Services/InputCursorHandler.cs

using Microsoft.AspNetCore.Components.Web;
using Microsoft.JSInterop;
using System.Threading.Tasks;

namespace cwebplusApp.Shared.Services {
    public class InputCursorHandler {

        private readonly IJSRuntime jsRuntime;

        public InputCursorHandler(IJSRuntime _jsRuntime) {
            this.jsRuntime = _jsRuntime;
        }

        public async Task<bool> OnKeyDownHandlerAsync(KeyboardEventArgs e) {
            var reference = DotNetObjectReference.Create(this);
            if (e.Key.Equals("Enter") || e.Key.Equals("ArrowRight")) {
                await jsRuntime.InvokeVoidAsync("MoveCursorToNextInput", reference, e.Key);
                return true;
            } else if (e.Key.Equals("ArrowLeft")) {
                await jsRuntime.InvokeVoidAsync("MoveCursorToPreviousInput", reference);
                return true;
            }
            return false;
        }

        public async Task OnConstrainedFieldKeyDownHandlerAsync(KeyboardEventArgs e) {
            if (!await OnKeyDownHandlerAsync(e)) {
                var reference = DotNetObjectReference.Create(this);
                await jsRuntime.InvokeVoidAsync("CheckConstrainedInput", reference, e.Key);
            }
        }
    }
}