namespace test { class Program { static void Main(string[] args) { var zoo1 = new zoo(); zoo1.animals = new List<animal>(); zoo1.animals.Add(new cat() { Name = "hello kitty", legs = 4 }); zoo1.animals.Add(new dog() { Name = "dog1", tail = true }); string json= fastJSON.JSON.Instance.ToJSON(zoo1); //序列化 var z = fastJSON.JSON.Instance.ToObject<zoo>(json); //反序列化 Console.WriteLine(z.animals[0].Name); Console.Read(); } } public class animal { public string Name { get; set; } } public class cat : animal { public int legs { get; set; } } public class dog : animal { public bool tail { get; set; } } public class zoo { public List<animal> animals { get; set; } }

internal object FastCreateInstance(Type objtype) { try { CreateObject c = null; if (_constrcache.TryGetValue(objtype, out c)) { return c(); } else { if (objtype.IsClass) { DynamicMethod dynMethod = new DynamicMethod("_", objtype, null); ILGenerator ilGen = dynMethod.GetILGenerator(); ilGen.Emit(OpCodes.Newobj, objtype.GetConstructor(Type.EmptyTypes)); ilGen.Emit(OpCodes.Ret); c = (CreateObject)dynMethod.CreateDelegate(typeof(CreateObject)); _constrcache.Add(objtype, c); } else // structs { DynamicMethod dynMethod = new DynamicMethod("_", MethodAttributes.Public | MethodAttributes.Static, CallingConventions.Standard, typeof(object), null, objtype, false); ILGenerator ilGen = dynMethod.GetILGenerator(); var lv = ilGen.DeclareLocal(objtype); ilGen.Emit(OpCodes.Ldloca_S, lv); ilGen.Emit(OpCodes.Initobj, objtype); ilGen.Emit(OpCodes.Ldloc_0); ilGen.Emit(OpCodes.Box, objtype); ilGen.Emit(OpCodes.Ret); c = (CreateObject)dynMethod.CreateDelegate(typeof(CreateObject)); _constrcache.Add(objtype, c); } return c(); } } catch (Exception exc) { throw new Exception(string.Format("Failed to fast create instance for type '{0}' from assemebly '{1}'", objtype.FullName, objtype.AssemblyQualifiedName), exc); } }