I have simple Blazor Web Application (Server Side, .NET 8, VS2022).
Here main page:

@page "/"
@using System.Timers
@rendermode InteractiveServer

<p>@StatusMessage</p>

<button class="btn btn-primary" @onclick="StartHandler">Start</button>

@code {
    private void StartHandler()
    {
        Countdown = 100;
        timerCounter.Interval = 1000;
        timerCounter.Elapsed += TimerCounter_Elapsed;
        timerCounter.AutoReset = true;
        timerCounter.Start();
    }
    private void TimerCounter_Elapsed(object? sender, ElapsedEventArgs e)
    {        
        Countdown--;
        StatusMessage = $"{Countdown}";
    }

    private Timer timerCounter = new Timer();
    private int Countdown = 0;    
    private string StatusMessage = "";
}

It should start the timer on button click and show countdown on the page.
But when I click the button nothing happened.
On next clicks it shows count like 99 or 97.
I don’t understand what is going.
Why the timer event doesn’t fire?
Thanks.

I tried countdown on button’s click and it works.
But I need the timer fires event.