Custom converters don't have to handle partial data

[tdykstra]

From @layomia in dotnet/runtime#39795 (comment)

In the existing JsonConverter model, custom converters do not have to worry about handling partial data, as the serializer passes all the data for the current JSON scope. Skip/TrySkip logic is unnecessary. We should consider adding a section about this in the docs.

The "read ahead" logic that the serializer performs to make this possible does have some perf implications. There has been some discussion around a new model to, among other benefits, enable more performant async-handling when custom converters are used - #1562. Relevant parts of the new model have been implemented internally in serializer, but exposing this publicly is not currently on the roadmap for System.Text.Json.

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Document Details

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• ID: 5de37d79-751f-e372-e866-efde28f4908c
• Version Independent ID: 678c4f23-764a-7ccd-0d6d-159a30957477
• Content: How to write custom converters for JSON serialization - .NET
• Content Source: docs/standard/serialization/system-text-json-converters-how-to.md
• Product: dotnet
• GitHub Login: @tdykstra
• Microsoft Alias: tdykstra