# Handling Async Operations Lite

> Provides essential async programming patterns with Task and ValueTask. Use when quickly referencing core async/await techniques without detailed explanations.

- Skill: `majiayu000/handling-async-operations-lite` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add majiayu000/handling-async-operations-lite`
- Raw SKILL.md: https://api.skillmd.com/api/skills/majiayu000/handling-async-operations-lite/raw
- Safety review: pending (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Productivity
- Author: majiayu000 (https://skillmd.com/u/majiayu000)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/majiayu000/handling-async-operations-lite

---


# Async Programming Essentials

## 1. Task vs ValueTask

```csharp
// General async: Use Task
public async Task<Data> LoadAsync() { }

// Frequent cache hits: Use ValueTask
public ValueTask<Data> GetAsync(string key)
{
    if (_cache.TryGetValue(key, out var cached))
        return new ValueTask<Data>(cached);

    return new ValueTask<Data>(LoadFromDbAsync(key));
}
```

## 2. CancellationToken

```csharp
public async Task<Data> LoadAsync(CancellationToken ct = default)
{
    ct.ThrowIfCancellationRequested();
    return await _httpClient.GetFromJsonAsync<Data>(url, ct);
}

// Timeout
using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(30));
await LongOperationAsync(cts.Token);
```

## 3. Anti-patterns

```csharp
// ❌ No async void
public async void BadMethod() { }

// ❌ No .Result, .Wait() (deadlock)
var result = GetDataAsync().Result;

// ✅ Use await
var result = await GetDataAsync();
```

> For details: See `/dotnet-async` skill