Serializing and DeSerializing The type "System.Threading.ReaderWriterLock"

Yoav

I am using a RBTree class in one of my projects (I did not write this class). The RBTree class contains a data member of the type "System.Threading.ReaderWriterLock". When I tried to serialize the RBTree I got an error: "An unhandled exception of type 'System.Runtime.Serialization.SerializationException' occurred in mscorlib.dll Additional information: The type System.Threading.ReaderWriterLock in Assembly mscorlib, Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b77a5c561934e089 is not marked as serializable." So this type is not marked as serializable. I there for marked it as "NonSerialized" in my RBTree class, and then I could serialize the RBTree. However, when I try to use the DeSerialized RBTree I get this error: "An unhandled exception of type 'System.NullReferenceException' occurred in Unreal Classes.exe Additional information: Object reference not set to an instance of an object." This error ocurs when the data member of type ReaderWriterLock is referenced. Obviously since it was not reconstructed together with the rest of the RBTree. Any ideas please?

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jcity44423y ago
Glad you got it working Yoav Ben Zvi. The first remark is just a temporary change until the serialization is working. I change the name of the file, or actually delete the file so it won't try to read it after I've made changes to the class it is serializing. If no fields have been added or deleted or changed inside the class, you can ignore the first remark. (Admittedly my first remark wasn't very clear ;) ) -Mike
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Yoav23y ago
Thanks for the help. I am not sure I understand your first remark. I thought that when I serialize into a file it written from the start, while losing any information that was stored in that file. Your second advice gave me the answer. I added to my RBTree class a public method that initialized the offending datamember. I used that method just after DeSerializing. I suppose that this has to be done for any class that is supossed to be serialized, but has nonserialized datamembers.
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jcity44423y ago
I've been going through some of the wonderful problems with serialization and deserialization as well. You have to be careful with serialization. Here are some hints in dealing with them 1. Make sure when you change anything in variables, you change the file name you are reading into. This gives you a fresh start. Otherwise strange null bugs pop up 2. When you make an object nonserialized you need to new it somewhere because it is skipped in the read. I tend to make my nonserialized objects static and assign them after the deserialize. Not sure this is good practice, but for singleton objects I suspect its okay. Hope this helps, -Mike
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