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c#ilmergebinary-serialization

BinaryFormatter.Deserialize "unable to find assembly" after ILMerge

I have a C# solution with a referenced dll (also C# with the same .Net version). When I build the solution and run the resulting exe, without merging the exe and the referenced dll, everything works fine.

Now I want to merge these into one exe. I run ILMerge and everything appears to work ok. I try to execute the exe and it seems to run just fine until it tries to deserialize an object defined in the referenced dll. 

using (Stream fstream = new FileStream(file_path, FileMode.Open))
{
    BinaryFormatter bf = new BinaryFormatter();
    return bf.Deserialize(fstream) as ControlledRuleCollection; 
    // throws unable to find assembly exception
}

Is there maybe some ILMerge option I'm missing here?

Solution

  • It sounds like you've serialized an object inside a DLL, then merged all of the assemblies with ILMerge and are now trying to deserialize that object. This simply won't work. The deserialization process for binary serialization will attempt to load the object's type from the original DLL. This DLL doesn't exist post ILMerge and hence the deserialization will fail.

    The serialization and deserialization process need to both operate pre or post merge. It can't be mixed