.NET 4.61升级至.NET Core 2.0后BreezeJS EF Core迁移问题求助

Hey there, sorry to hear you're stuck with unresolved BreezeJS issues after upgrading your backend. Moving from .NET Framework to Core can throw unexpected curveballs, especially with libraries like Breeze that have deep framework integrations. Let’s start by aligning on your setup, then cover common pain points and what details you’ll need to share for targeted help.

First, let’s recap your migration steps to make sure we’re on the same page:

• Upgraded from .NET 4.6.1 to .NET Core 2.0
• Used a .NET Standard class library with the Scaffold-DbContext command to set up your data layer (including all necessary dependencies)
• Created a .NET Core 2.0 Web API project with Breeze and EF Core dependencies
• Migrated your existing controllers from the original .NET Framework project

Since you mentioned two specific issues that aren’t covered in online resources, here are some common Breeze + .NET Core 2.0 pitfalls to check first, plus what info we’ll need to diagnose your exact problems:

Common BreezeJS Migration Issues & Quick Fixes #

1. Metadata Generation Failures #

Breeze relies entirely on accurate metadata to interact with your entities, and this process works differently in .NET Core vs. .NET Framework:

• Double-check that your DbContext is configured with Breeze’s BreezeQueryFilter and that your controller has a Metadata() action (usually paired with the [BreezeController] attribute) to expose metadata to the client.
• Verify that your entity classes have the correct data annotations—some System.ComponentModel.DataAnnotations attributes behave differently in .NET Core, and you might need to switch to EF Core-specific attributes for relationships or key definitions.
• Ensure Scaffold-DbContext didn’t omit any critical relationships or key constraints that Breeze depends on to build valid metadata.

2. Query or Serialization Errors #

If you’re hitting errors when running Breeze queries or serializing entities:

• Confirm you’re using the correct Breeze NuGet packages for .NET Core—stick to Breeze.AspNetCore and Breeze.Persistence.EFCore; avoid mixing in .NET Framework-specific Breeze packages.
• Check for circular references in your entities. EF Core’s serialization is stricter than .NET Framework’s, so you may need to configure JsonSerializerSettings to ignore circular references or add [JsonIgnore] to appropriate properties.
• Make sure your controller actions return IQueryable<T> with the [EnableBreezeQuery] attribute, and don’t manually enumerate queries before returning them—this breaks Breeze’s ability to compose queries client-side.

What to Share for Targeted Help #

To help us nail down your specific issues, please add:

• Exact error messages (full stack traces are ideal)
• Code snippets from your problematic controllers, DbContext setup, or relevant entity classes
• Details on which operations are failing (e.g., fetching metadata, saving changes, executing a specific query)

Once you share those specifics, we can dive into tailored solutions for your problems!

内容的提问来源于stack exchange，提问作者Amirreza