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Try the counter

In the running app, navigate to the Counter page by clicking the Counter tab in the sidebar on the left. The following page should then be displayed:

The Counter page presents a Click me button to increment the count showed on the page.

Select the Click me button to increment the count without a page refresh. Incrementing a counter in a webpage normally requires writing JavaScript, but with Blazor you can use C#.

You can find the implementation of the Counter component at Counter.razor file located inside the Components/Pages directory.

Components/Pages/Counter.razor
@page "/counter"
@rendermode InteractiveServer

<PageTitle>Counter</PageTitle>

<h1>Counter</h1>

<p role="status">Current count: @currentCount</p>

<button class="btn btn-primary" @onclick="IncrementCount">Click me</button>

@code {
    private int currentCount = 0;

    private void IncrementCount()
    {
        currentCount++;
    }
}

A request for /counter in the browser, as specified by the @page directive at the top, causes the Counter component to render its content. The @rendermode directive enables interactive server rendering for the component, so that it can handle user interface events from the browser.

Each time the Click me button is selected:

  • The onclick event is fired.
  • The IncrementCount method is called.
  • The currentCount is incremented.
  • The component is rendered to show the updated count.
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