<p>Current count in component: @Count</p>

<button @onclick="Increment">+</button>
<button @onclick="Decrement">-</button>

@code {
    [Parameter]
    public int Count { get; set; }

    [Parameter]
    public EventCallback<int> CountChanged { get; set; }

    private void Increment()
    {
        CountChanged.InvokeAsync(Count + 1);
    }

    private void Decrement()
    {
        CountChanged.InvokeAsync(Count - 1);
    }
}
