JsonReaderExceptions in JsonNodeExtensions spoils debugging in Visual Studio

[aureole82]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

We introduced OpenAPI document generation with Microsoft.AspNetCore.OpenApi (and replaced Swashbuckle).
But now we get tons of

System.Text.Json.JsonReaderException: ''E' is an invalid start of a value. LineNumber: 0 | BytePositionInLine: 0.'

The problem:

aspnetcore/src/OpenApi/gen/XmlCommentGenerator.Emitter.cs

Line 447 in 08cadfe

file static class JsonNodeExtensions

calls JsonNode.Parse(json) blindly, what throws JsonReaderException if you have xml comments like <example>EN</example>. Even if it's caught it spoils debugging in Visual Studio and spams the logging.

Expected Behavior

Stick to your own guidelines!!!
https://learn.microsoft.com/dotnet/standard/design-guidelines/exception-throwing

❌ DO NOT use exceptions for the normal flow of control, if possible.

---

I would suggest

1. Consider the schema! If it's a string always call JsonValue.Create(exampleString). Nobody has <example>"EN"</example> XML comments!
2. Or more flexible: If string and
   • quoted: "EN" → JsonNode.Parse(json),
   • otherwise EN → JsonValue.Create(exampleString).
3. Maybe you could ask the JSON guys for JsonNode.TryParse()?
4. Move your JsonNodeExtensions into your code.
   (Sweeping it under your rug is never good, but it would at least help me.)

Steps To Reproduce

Add a property to your API like

/// <summary> Language of the product. </summary>
/// <example>EN</example>
public required string Language { get; }

and run the API in Visual Studio with all exception settings active.

Exceptions (if any)

System.Text.Json.JsonReaderException: ''E' is an invalid start of a value. LineNumber: 0 | BytePositionInLine: 0.'

.NET Version

10.0.102

Anything else?

No response