<PackageReference Include="Google.Protobuf" Version="3.35.1" />

Google.Protobuf.Reflection.ExtensionCollection

public sealed class ExtensionCollection
A collection to simplify retrieving the descriptors of extensions in a descriptor for a message
public IList<FieldDescriptor> UnorderedExtensions { get; }

Returns a readonly list of all the extensions defined in this type in the order they were defined in the source .proto file

public IList<FieldDescriptor> GetExtensionsInDeclarationOrder(MessageDescriptor descriptor)

Returns a readonly list of all the extensions define in this type that extend the provided descriptor type in the order they were defined in the source .proto file

public IList<FieldDescriptor> GetExtensionsInNumberOrder(MessageDescriptor descriptor)

Returns a readonly list of all the extensions define in this type that extend the provided descriptor type in ascending field order