WCF deserialization, does not call constructors, how to resolve class initialization problems

WCF deserialization, does not call the constructor, how to solve the class initialization problem? Encountered this problem, found some information to finally solve the problem. The key is two features:

[OnDeserializing]

[OnDeserialized]

Check the code:

   [DataContract] public class Mydatatype {[DataMember] private list<int> nval = new List<in        T> ();        Public Mydatatype () {nval.add (12);  } [ondeserializing] void BeginInit (StreamingContext sc) {Console.WriteLine ("Same to begin        Constructor "); } [ondeserialized] void EndInit (StreamingContext sc) {Console.WriteLine ("Same to end Cons        Tructor ");            } [DataMember] public int Initmemberdata {get {return 0;}                set {Object obj = this;            Console.WriteLine ("Initmemberdata:set.");        }} private int intv;            [DataMember] public int int {get {return intv;                } set {Console.WriteLine ("Int:set.");        if (nval = = null) Intv = value;    }} string _str;            [DataMember] public string String {get {return _str;}                set {Console.WriteLine ("String:set.");             _str = value;        }} long _long;            [DataMember] public long Long {get {return _long;}                set {Console.WriteLine ("Long:set.");             _long = value; }        }           }

Output when deserializing:

WCF deserialization, does not call constructors, how to resolve class initialization problems