Blazor: Poll a server's object in an interval?

Question

It seems that Blazor makes it easy for the client to call a server's method using something called SignalR underneath. But when I searched if Blazor does that for the other direction, the answer was that Blazor does not do that and I have to implement it myself using SignalR. So, I thought about polling.

That is, I like to read a property or call a method in the server's object at an interval to determine if something has changed. To test this, I added this property to the WeatherForecastService class. The property increases every time when read.

    int _Value = 0;
    public int Value
    {
        get
        {
            _Value++;
            return _Value;
        }
    }

In the weather tablet sample plage, I removed the code to display the weather and added this.

<p>This component demonstrates fetching data from a service.</p>

<div>Value = @this.Value</div>

@code {
    private int Value = 0;

    protected override async Task OnInitializedAsync()
    {
        System.Timers.Timer t = new System.Timers.Timer();
        t.Elapsed += (s, e) => { Value = ForecastService.Value; };
        t.Interval = 1000;
        t.Start();
    }
}

And it did not work. I found an existing question, but it uses F# which I don't understand, and I don't know what ClientTImer is, so the answer was not helpful to me.

Answer 1

t.Elapsed += async (s, e) => 
    { 
       Value = ForecastService.Value; 
       await InvokeAsync(StateHasChanged); 
    };