c# - Deserialization of an array always gives an array of nulls -

i have custom abstract base class sub classes i've made serializable/deseriablizeable iserializable. when serialization/deserialization of single instances of class' sub classes, works fine. however, when array of them end array of nulls on deserialization. serialization done binaryformatter.

the items contained within a:

public observablecollection<trade> trades { get; private set; } 

on serialization done in getobjectdata on serializationinfo parameter:

trade[] trades = (trade[])trades.toarray<trade>();             info.addvalue("trades", trades); 

and on deserialization done in serialization constructor on serializationinfo parameter:

trade[] trades = (trade[])info.getvalue("trades", typeof(trade[]));              foreach (trade t in trades)             {                 trades.add(t);             } 

deserialization gives me array of nulls , mentioned earlier, single item serializes , deseriaizes fine code:

serialization (getobjectdata method):

info.addvalue("trade", trades.first<trade>()); 

deserialization (serialization constructor):

trade t = (trade)info.getvalue("trade", typeof(trade));             trades.add(t); 

is common problem? seem find no occurrences of else running in @ least. there solution :) , if need supply more information/code tell me.

thanks!

array deserializes first. inner deserialization done. when try access items, null.

and idea use [ondeserialized] attribute on method, builds other properies. , here example:

[serializable] public class testclass : iserializable {     private trade[] _innerlist;     public observablecollection<trade> list { get; set; }      public testclass()     { }      [ondeserialized]     private void setvaluesondeserialized(streamingcontext context)     {         this.list = new observablecollection<trade>(_innerlist);         this._innerlist = null;     }      protected testclass(serializationinfo info, streamingcontext context)     {         var value = info.getvalue("inner", typeof(trade[]));         this._innerlist = (trade[])value;     }      public void getobjectdata(serializationinfo info, streamingcontext context)     {         info.addvalue("inner", this.list.toarray());     } }