我正在检查 protobuf-net 是否可以替代 DataContracts。除了出色的性能外，它确实是一个整洁的库。我唯一的问题是 .NET 序列化程序不会对它们当前正在反序列化的内容做出任何假设。特别是包含对类型化对象的引用的对象是一个问题。
[DataMember(Order = 3)]
public object Tag1 // The DataContract did contain a object which becomes now a SimulatedObject
{
get;
set;
}
我尝试使用带有一点通用帮助器的协议缓冲区来模拟对象，该帮助器确实将每种可能的类型存储在不同的强类型字段中。
这是处理反/序列化为许多不同的不相关类型的字段的推荐方法吗？
下面是一个 SimulatedObject 的示例代码，它最多可以容纳 10 种不同的类型。
using System;
using System.Collections.Generic;
using System.IO;
using System.Runtime.Serialization;
using ProtoBuf;
using System.Diagnostics;
[DataContract]
public class SimulatedObject<T1,T2,T3,T4,T5,T6,T7,T8,T9,T10>
{
[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<bool, Other, Other, Other, Other, Other, Other, Other, Other, SomethingDifferent> Tag1 // Can contain up to 10 different types
{
get;
set;
}
[DataMember(Order = 4)]
public List<string> 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<string> { "First", "Second", "Third" },
Tag1 = new SimulatedObject<bool, Other, Other, Other, Other, Other, Other, Other, Other, SomethingDifferent>
{
Data = new Other { OtherData = "String value "}
}
};
const int Runs = 1000 * 1000;
var stream = new MemoryStream();
var sw = Stopwatch.StartNew();
Serializer.Serialize<Customer>(stream, c);
sw = Stopwatch.StartNew();
for (int i = 0; i < Runs; i++)
{
stream.Position = 0;
stream.SetLength(0);
Serializer.Serialize<Customer>(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<Customer>(stream);
sw = Stopwatch.StartNew();
for (int i = 0; i < Runs; i++)
{
stream.Position = 0;
var newCust = Serializer.Deserialize<Customer>(stream);
}
sw.Stop();
Console.WriteLine("Read object with Protocol buffer deserializer: {0} objects did take {1}s", Runs, sw.Elapsed.TotalSeconds);
}
}