Sorting a List of Custom Objects with Optional Properties in C# - Handling Nulls Properly
I've looked through the documentation and I'm still confused about Can someone help me understand I'm collaborating on a project where I've searched everywhere and can't find a clear answer. I tried several approaches but none seem to work. I'm working on a C# application using .NET 6, where I need to sort a list of custom objects based on two properties: `Name` and an optional `Age`. The scenario arises when the `Age` property is null. I want the sorting to prioritize non-null `Age` values first and then sort by `Name` alphabetically. However, I'm working with unexpected behavior with null `Age` values causing them to be mixed in incorrectly with the sorted results. Here’s my current implementation: ```csharp public class Person { public string Name { get; set; } public int? Age { get; set; } } List<Person> people = new List<Person> { new Person { Name = "Alice", Age = 30 }, new Person { Name = "Bob", Age = null }, new Person { Name = "Charlie", Age = 25 }, new Person { Name = "David", Age = null }, }; var sortedPeople = people.OrderBy(p => p.Age.HasValue ? 0 : 1) .ThenBy(p => p.Age) .ThenBy(p => p.Name) .ToList(); ``` The scenario I’m working with is that the sorting logic for `Age` does not seem to sort the list as intended. Instead of seeing all people with non-null `Age` values at the top, I get a mixed order, especially when the names are similar. I expected to see all entries with a valid `Age` first in ascending order, followed by those with null `Age`, sorted by name. I’ve tried various combinations of `OrderBy` and `ThenBy`, even adding `Age.HasValue` checks to handle the nulls better, but the output still isn’t what I anticipated. The final list sometimes places entries with null `Age` before entries with valid `Age` when their names are alphabetically sorted. Can anyone help clarify what might be going wrong in my sorting logic and suggest a proper way to achieve the desired order? I’ve also ensured I’m using the latest C# and .NET version, so there should be no compatibility issues. Any help would be greatly appreciated! This is part of a larger application I'm building. Thanks in advance! The project is a web app built with C#. Any pointers in the right direction? I'm on Ubuntu 22.04 using the latest version of C#. I'm open to any suggestions. This is part of a larger service I'm building. Hoping someone can shed some light on this.