InvalidCastException when serializing and deserializing
c#, serialization
Solution
You have loaded the same assembly twice, in different loader contexts. E.g. you happened to load the XXX.Auditing with `Assembly.LoadFrom()` first, and then some other (or your) assembly loaded it normally. In fact, the binary deserializer could be the one who loaded the assembly a second time, though I wouldn't know why (no experience with ASP.NET).
Problem
I have this code: ``` public byte[] SerializeToBlob() { using (var buffer = new MemoryStream()) { var formatter = new BinaryFormatter(); formatter.Serialize(buffer, this); buffer.Position = 0; return buffer.ToArray(); } } public static ActionData DeserializeFromBlob(byte[] state) { using (var buffer = new MemoryStream(state)) { var formatter = new BinaryFormatter(); var result = formatter.Deserialize(buffer); return (ActionData) result; } } ``` And am calling it as follows: ``` byte[] actionDataBlob = ad.SerializeToBlob(); var ad1 = ActionData.DeserializeFromBlob(actionDataBlob); ``` However, I get an InvalidCastException when it tries to cast the deserialized object to its type: [A]ActionData cannot be cast to [B]ActionData. Type A originates from 'XXXX.XXXX.Auditing, Version=1.0.76.0, Culture=neutral, PublicKeyToken=null' in the context 'Default' at location 'C:\Users\Craig\AppData\Local\Temp\Temporary ASP.NET Files\root\5d978e5b\ffc57fe1\assembly\dl3\2b1e5f8f\102c846e_9506ca01\XXXX.XXXX.Auditing.DLL'. Type B originates from 'XXXX.XXXX.Auditing, Version=1.0.76.0, Culture=neutral, PublicKeyToken=null' in the context 'LoadNeither' at location 'F:\Visual Studio Projects\XXXXXXXXX\source\XXXX.XXXX.SilverlightClient.Web\bin\XXXX.XXXX.Auditing.dll'. (XXXX.XXXX is there to obscure the client's name) What gives? I've now asked a related question here: How should I serialize some simple auditing data for storing in a SQL table?