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POprotobuf-net and de/serializing objects
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  1. POprotobuf-net and de/serializing objects
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    copied!<p>I am checking if protobuf-net can be an in place replacement for DataContracts. Besides the excellent performance it is really a neat library. The only issue I have is that the .NET serializers do not make any assumptions what they are currently de/serializing. Especially objects which do contain reference to the typed object are a problem. </p> <pre><code>[DataMember(Order = 3)] public object Tag1 // The DataContract did contain a object which becomes now a SimulatedObject { get; set; } </code></pre> <p>I tried to mimic object with protocol buffers with a little generic helper which does store for each possible type in a different strongly typed field. </p> <p>Is this an recommended approach to deal with fields which de/serialize into a number of different not related types? </p> <p>Below is the sample code for a SimulatedObject which can hold up to 10 different types. </p> <pre><code>using System; using System.Collections.Generic; using System.IO; using System.Runtime.Serialization; using ProtoBuf; using System.Diagnostics; [DataContract] public class SimulatedObject&lt;T1,T2,T3,T4,T5,T6,T7,T8,T9,T10&gt; { [DataMember(Order = 20)] byte FieldHasValue; // the number indicates which field actually has a value [DataMember(Order = 1)] T1 I1; [DataMember(Order = 2)] T2 I2; [DataMember(Order = 3)] T3 I3; [DataMember(Order = 4)] T4 I4; [DataMember(Order = 5)] T5 I5; [DataMember(Order = 6)] T6 I6; [DataMember(Order = 7)] T7 I7; [DataMember(Order = 8)] T8 I8; [DataMember(Order = 9)] T9 I9; [DataMember(Order = 10)] T10 I10; public object Data { get { switch(FieldHasValue) { case 0: return null; case 1: return I1; case 2: return I2; case 3: return I3; case 4: return I4; case 5: return I5; case 6: return I6; case 7: return I7; case 8: return I8; case 9: return I9; case 10: return I10; default: throw new NotSupportedException(String.Format("The FieldHasValue field has an invlaid value {0}. This indicates corrupt data or incompatible data layout chagnes", FieldHasValue)); } } set { I1 = default(T1); I2 = default(T2); I3 = default(T3); I4 = default(T4); I5 = default(T5); I6 = default(T6); I7 = default(T7); I8 = default(T8); I9 = default(T9); I10 = default(T10); if (value != null) { Type t = value.GetType(); if (t == typeof(T1)) { FieldHasValue = 1; I1 = (T1) value; } else if (t == typeof(T2)) { FieldHasValue = 2; I2 = (T2) value; } else if (t == typeof(T3)) { FieldHasValue = 3; I3 = (T3) value; } else if (t == typeof(T4)) { FieldHasValue = 4; I4 = (T4) value; } else if (t == typeof(T5)) { FieldHasValue = 5; I5 = (T5) value; } else if (t == typeof(T6)) { FieldHasValue = 6; I6 = (T6) value; } else if (t == typeof(T7)) { FieldHasValue = 7; I7 = (T7) value; } else if (t == typeof(T8)) { FieldHasValue = 8; I8 = (T8) value; } else if (t == typeof(T9)) { FieldHasValue = 9; I9 = (T9) value; } else if (t == typeof(T10)) { FieldHasValue = 10; I10 = (T10) value; } else { throw new NotSupportedException(String.Format("The type {0} is not supported for serialization. Please add the type to the SimulatedObject generic argument list.", t.FullName)); } } } } } [DataContract] class Customer { /* [DataMember(Order = 3)] public object Tag1 // The DataContract did contain a object which becomes now a SimulatedObject { get; set; } */ [DataMember(Order = 3)] public SimulatedObject&lt;bool, Other, Other, Other, Other, Other, Other, Other, Other, SomethingDifferent&gt; Tag1 // Can contain up to 10 different types { get; set; } [DataMember(Order = 4)] public List&lt;string&gt; Strings { get; set; } } [DataContract] public class Other { [DataMember(Order = 1)] public string OtherData { get; set; } } [DataContract] public class SomethingDifferent { [DataMember(Order = 1)] public string OtherData { get; set; } } class Program { static void Main(string[] args) { Customer c = new Customer { Strings = new List&lt;string&gt; { "First", "Second", "Third" }, Tag1 = new SimulatedObject&lt;bool, Other, Other, Other, Other, Other, Other, Other, Other, SomethingDifferent&gt; { Data = new Other { OtherData = "String value "} } }; const int Runs = 1000 * 1000; var stream = new MemoryStream(); var sw = Stopwatch.StartNew(); Serializer.Serialize&lt;Customer&gt;(stream, c); sw = Stopwatch.StartNew(); for (int i = 0; i &lt; Runs; i++) { stream.Position = 0; stream.SetLength(0); Serializer.Serialize&lt;Customer&gt;(stream, c); } sw.Stop(); Console.WriteLine("Data Size with Protocol buffer Serializer: {0}, {1} objects did take {2}s", stream.ToArray().Length, Runs, sw.Elapsed.TotalSeconds); stream.Position = 0; var newCustw = Serializer.Deserialize&lt;Customer&gt;(stream); sw = Stopwatch.StartNew(); for (int i = 0; i &lt; Runs; i++) { stream.Position = 0; var newCust = Serializer.Deserialize&lt;Customer&gt;(stream); } sw.Stop(); Console.WriteLine("Read object with Protocol buffer deserializer: {0} objects did take {1}s", Runs, sw.Elapsed.TotalSeconds); } } </code></pre>
 

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