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SerializationFormat.Binary is obsolete

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SerializationFormat.Binary is obsolete for DataTable and DataSet. Binary serialization relies on BinaryFormatter, which is insecure. If you use SerializationFormat.Binary in your code, obsoletion warning SYSLIB0038 will be generated at compile time.

In addition, an InvalidEnumArgumentException is thrown at run time if you:

Previous behavior

Previously, DataTable and DataSet could be serialized and deserialized with their RemotingFormat property set to SerializationFormat.Binary, which used BinaryFormatter under the hood.

New behavior

Starting in .NET 7, if you attempt to serialize or deserialize DataTable and DataSet with their RemotingFormat property set to SerializationFormat.Binary, an InvalidEnumArgumentException is thrown.

Version introduced

.NET 7

Type of breaking change

This change can affect source compatibility and binary compatibility.

Reason for change

SerializationFormat.Binary is implemented via BinaryFormatter, which is insecure and being obsoleted across the entire .NET stack.

If your code uses SerializationFormat.Binary, switch to using SerializationFormat.Xml or use another method of serialization.

Otherwise, you can set the Switch.System.Data.AllowUnsafeSerializationFormatBinary AppContext switch. This switch lets you opt in to allowing the use of SerializationFormat.Binary, so that code can work as before. However, this switch will be removed in .NET 8. For information about setting the switch, see AppContext for library consumers.

Affected APIs

See also