MSDN Community

Hi everyone,

I'm looking for some insights and best practices regarding asynchronous programming in C#. Specifically, I'm interested in:

• When to use async/await vs. traditional threading.
• Common pitfalls and how to avoid them (e.g., deadlocks, context switching issues).
• Best patterns for error handling in async methods.
• Tips for optimizing performance with async operations.

Any advice, code examples, or links to valuable resources would be greatly appreciated!

Thanks!

Hey John,

Great topic! async/await is generally preferred for I/O-bound operations and operations that would otherwise block the UI thread. Traditional threading is more suitable for CPU-bound work where you need fine-grained control or want to leverage multiple cores directly.

One common pitfall is accidentally blocking the calling thread by using .Result or .Wait() on an async method. This can lead to deadlocks, especially in UI applications or ASP.NET contexts. Always use await when calling async methods if possible.

For error handling, propagating exceptions through the async chain and catching them where you await the result is usually the cleanest approach. Consider using try-catch blocks around your await calls.

Here's a simple example:

async Task ProcessDataAsync()
{
    try
    {
        string result = await FetchDataAsync();
        Console.WriteLine("Data fetched: " + result);
    }
    catch (HttpRequestException ex)
    {
        Console.Error.WriteLine($"Error fetching data: {ex.Message}");
    }
}
                        

Thanks Sarah! That's very helpful. The point about .Result and .Wait() is crucial. I've definitely seen situations where that caused issues.

What about cancellation? How do you best handle cancelling long-running async operations?