若直接使用await返回结果，异步编程是否有收益？全异步是否必要？

Great question—this is a super common point of confusion, so let’s break it down based on where your code is running:

Scenarios Where Async Does Deliver Clear Value #

Even if you don’t have additional code after the await keyword, async/await can still be extremely valuable depending on your application type:

• UI Applications (WPF, WinForms, Blazor WASM, MAUI)
  UI threads are single-threaded—if you call a synchronous IO operation (like a web API request) directly, the entire UI freezes until the operation finishes. Using await here releases the UI thread immediately, letting it handle user interactions (clicks, scrolling, etc.) while waiting for the IO result. Even if there’s no code after await, keeping the UI responsive is a massive win for user experience.

• ASP.NET Core (Server-Side)
  ASP.NET Core uses a thread pool to handle incoming requests. When you await an IO-bound operation (like database calls or web API requests), the underlying thread gets released back to the pool to handle other incoming requests. This drastically boosts server throughput—instead of tying up a thread waiting for IO, the same thread can process more requests in parallel. Even if your method ends right after await, your server can handle far more concurrent traffic than with synchronous code.

Scenarios Where Async Provides Little to No Benefit #

There are edge cases where async doesn’t offer meaningful gains when there’s no code after await:

• Simple Console Applications (no concurrent work)
  If you’re running a console app where the main thread just waits for a single async operation to complete (with no other background tasks running), the behavior is almost identical to calling the synchronous equivalent. The main thread will still block waiting for the result, so you don’t get any throughput or responsiveness benefits here.

Key Takeaway #

The core benefit of async/await isn’t about having code after the await—it’s about freeing up threads during IO-bound operations. For most real-world apps (UI or server-side), this leads to better responsiveness or higher throughput, even if you don’t have additional code after the await call.

Of course, if an API only provides an async version, you have no choice—but even when synchronous options exist, it’s worth choosing async in UI or server contexts for those core benefits.

内容的提问来源于stack exchange，提问作者AlfredBr