Add JsonSourceGenerationOptions.UseStringEnumConverter

[eiriktsarpalis]

This PR:

• Implements the JsonSourceGenerationOptionsAttribuet.UseStringEnumConverter property.
• Implements the JsonNumberEnumConverter<TEnum> converter.

Fix #87195.

[ghost]

Note regarding the new-api-needs-documentation label:

This serves as a reminder for when your PR is modifying a ref *.cs file and adding/modifying public APIs, please make sure the API implementation in the src *.cs file is documented with triple slash comments, so the PR reviewers can sign off that change.

[ghost]

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Issue Details

---

This PR:

• Implements the JsonSourceGenerationOptionsAttribuet.UseStringEnumConverter property.
• Implements the JsonNumberEnumConverter<TEnum> converter.

Fix #87195.

Author:	eiriktsarpalis
Assignees:	-
Labels:	area-System.Text.Json, new-api-needs-documentation
Milestone:	-

[svrooij]

Any idea when such a feature will be rolled out?

[eiriktsarpalis]

It should be available starting with .NET 8 Preview 7

[svrooij]

@eiriktsarpalis any chance it will be backported to .NET7? Thanks for the super fast answer.

[eiriktsarpalis]

The bar for servicing .NET 7 is security issues or substantially broken .NET 7 features. You can still use the latest STJ version in .NET 7 using the NuGet package though.