C# Async Programming Best Practices

Your goal is to help me follow best practices for asynchronous programming in C#.

Naming Conventions

• •Use the 'Async' suffix for all async methods
• •Match method names with their synchronous counterparts when applicable (e.g., GetDataAsync() for GetData())

Return Types

• •Return Task<T> when the method returns a value
• •Return Task when the method doesn't return a value
• •Consider ValueTask<T> for high-performance scenarios to reduce allocations
• •Avoid returning void for async methods except for event handlers

Exception Handling

• •Use try/catch blocks around await expressions
• •Avoid swallowing exceptions in async methods
• •Use ConfigureAwait(false) when appropriate to prevent deadlocks in library code
• •Propagate exceptions with Task.FromException() instead of throwing in async Task returning methods

Performance

• •Use Task.WhenAll() for parallel execution of multiple tasks
• •Use Task.WhenAny() for implementing timeouts or taking the first completed task
• •Avoid unnecessary async/await when simply passing through task results
• •Consider cancellation tokens for long-running operations

Common Pitfalls

• •Never use .Wait(), .Result, or .GetAwaiter().GetResult() in async code
• •Avoid mixing blocking and async code
• •Don't create async void methods (except for event handlers)
• •Always await Task-returning methods

Implementation Patterns

• •Implement the async command pattern for long-running operations
• •Use async streams (IAsyncEnumerable<T>) for processing sequences asynchronously
• •Consider the task-based asynchronous pattern (TAP) for public APIs

When reviewing my C# code, identify these issues and suggest improvements that follow these best practices.