Blazor teaser

Blazor lets you build interactive UIs with C# instead of JavaScript—components run WebAssembly in the browser (Blazor WASM) or on the server via SignalR (Blazor Server).

Two hosting models

• Blazor Server — UI events round-trip to server; small download, needs persistent connection
• Blazor WebAssembly — .NET runs in browser; offline-capable, larger initial payload

Component sketch

@page "/counter"
<h1>Count: @count</h1>
<button @onclick="Increment">+</button>
@code {
    int count;
    void Increment() => count++;
}

When to consider Blazor

.NET-only teams wanting shared types between API and UI; internal tools; scenarios where JavaScript churn is costly. Many public SPAs still use React/Vue with ASP.NET Core APIs.

Important interview questions and answers

1. Q: Blazor vs React?
   A: Blazor uses C# components; React uses JS/TS with huge ecosystem—pick based on team skills and UI needs.
2. Q: Blazor Server latency?
   A: Every interaction hits server—fine on LAN, sensitive on high-latency mobile networks.

Self-check

1. Name the two main Blazor hosting models.
2. When might you still pair ASP.NET API with React?