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How to Handle Circular References in Entity Framework Core with Lazy Loading Enabled?

👀 Views: 2 💬 Answers: 1 📅 Created: 2025-06-10
entity-framework-core json serialization lazy-loading C#

I'm currently working on a C# project using Entity Framework Core 6.0 with lazy loading enabled, and I've run into an scenario with circular references causing a `JsonException` when trying to serialize the data to JSON... My model consists of `Post` and `Comment` entities where a `Post` can have many `Comments`, and each `Comment` has a reference back to its `Post`. Here's a simplified version of my models: ```csharp public class Post { public int Id { get; set; } public string Title { get; set; } public virtual ICollection<Comment> Comments { get; set; } = new List<Comment>(); } public class Comment { public int Id { get; set; } public string Content { get; set; } public virtual Post Post { get; set; } } ``` When I try to retrieve a `Post` along with its `Comments` and serialize it using `System.Text.Json`, I encounter the following behavior: ``` System.Text.Json.JsonException: The JSON value could not be converted to System.Collections.Generic.ICollection`1[Comment]. ``` I’ve tried disabling lazy loading, but that doesn't seem to help and makes my query less efficient. I also considered adding the `[JsonIgnore]` attribute to the `Post` property in the `Comment` class, but then I'd lose the reference to the `Post` when serializing. Is there a recommended way to handle this situation without losing the necessary information while still being able to serialize the objects correctly? I've looked into using DTOs or custom JSON converters but I'm unsure how to implement it correctly in this scenario. Any suggestions? For context: I'm using C# on Ubuntu. What am I doing wrong?