Remove BinaryFormatter serialization examples

[gewarren]

BinaryFormatter should no longer be used because it's insecure. We should remove/update any code snippets in our docs.

https://learn.microsoft.com/en-us/dotnet/standard/serialization/binaryformatter-security-guide

Examples of articles to update:

• https://learn.microsoft.com/en-us/dotnet/standard/base-types/how-to-round-trip-date-and-time-values
• https://learn.microsoft.com/en-us/dotnet/standard/serialization/basic-serialization - recommend archival
• https://learn.microsoft.com/en-us/dotnet/csharp/programming-guide/concepts/serialization/walkthrough-persisting-an-object-in-visual-studio (usage data)
• https://learn.microsoft.com/en-us/dotnet/visual-basic/programming-guide/concepts/serialization/walkthrough-persisting-an-object-in-visual-studio - 178 PVs in November, suggest removing
• https://learn.microsoft.com/en-us/dotnet/framework/wcf/feature-details/controlling-serialization-and-deserialization-with-serializationbinder - 125 page views in November, suggest removing
• https://learn.microsoft.com/en-us/dotnet/framework/wcf/samples/usage-of-serialization-binder - 49 page views in November, suggest removing it
  • ...and the sample it's supposed to link to
• https://learn.microsoft.com/en-us/dotnet/standard/serialization/how-to-determine-if-netstandard-object-is-serializable - 193 PVS in November, suggest removing
• https://learn.microsoft.com/en-us/dotnet/core/extensions/globalization - Recommend updating the examples not to use BinaryFormatter
• All the hits in the dotnet/docs-desktop repo - https://github.com/dotnet/docs-desktop/search?q=binaryformatter
  • Opened Don't recommend BinaryFormatter docs-desktop#1551 to address the recommended use of BinaryFormatter for serialization. The remaining hits are in auto-generated .resx files and there's an open epic to remove this still existing functionality from WinForms.
• Samples in the dotnet/samples repo - https://github.com/dotnet/samples/search?q=binaryformatter - Like the docs-desktop repo, most hits are in auto-generated .resx files. The one sample is fixed by Update sample to use JSON serialization instead of binary samples#5617.

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Associated WorkItem - 45472