ASP.NET Core Web API Interview Question #109

What is the difference between Task and ValueTask in API code?

Dependency Injection, Services, EF Core, Async & Data Access Mid-Level Intermediate

Quick Interview Answer

Task is the standard representation of an asynchronous operation and is appropriate for most Web API application code. ValueTask can reduce allocations in specialized cases where operations frequently complete synchronously, but it has more complex usage rules.

Detailed Explanation

Do not replace Task with ValueTask without evidence that the optimization matters. Clarity and correctness are usually more important than speculative allocation savings.

Code Example

public Task<Product?> GetAsync(
    int id,
    CancellationToken token)
{
    return _db.Products.SingleOrDefaultAsync(
        x => x.Id == id, token);
}