Below block of code is Blazor documentation. But I am not able to figure out how and on what basis 'text' route parameter assigns value to the Text property. 

```
@page "/RouteParameter"
@page "/RouteParameter/{text}"

<h1>Blazor is @Text!</h1>

@code {
    [Parameter]
    public string Text { get; set; }

    protected override void OnInitialized()
    {
        Text = Text ?? "fantastic";
    }
}

```