Remove DataSet/DataTable code paths for SerializationFormat.Binary

[roji]

Following the obsoletion of SerializationFormat.Binary and putting it behind an appcontext switch in .NET 7.0 (#39289), we should remove the code paths which support it, and which contain BinaryFormatter usage.

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Issue Details

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Following the obsoletion of SerializationFormat.Binary and putting it behind an appcontext switch in .NET 7.0 (#39289), we should remove the code paths which support it, and which contain BinaryFormatter usage.

Author:	roji
Assignees:	roji
Labels:	area-System.Data
Milestone:	Future

[stephentoub]

cc: @GrabYourPitchforks

[Wraith2]

Is #39397 what you're looking to do?

[roji]

@Wraith2 more or less, yeah - but with a more gradual approach. For .NET 7.0 I've just merged #65139, which both obsoletes and adds a runtime check to throw - but still allows an appcontext switch to be used to opt into using SerializationFormat.Binary. This issue would remove the code entirely in .NET 8.0, so even the appcontext switch would no longer work.

[Wraith2]

Ok. I was just wondering if that one would have saved you from having to do all the work, seems not.