c# - Weird dictionary ContainsKey issue -

before start, i'd clarify not other "similar" questions out there. i've tried implementing each approach, phenomena getting here weird.

i have dictionary containskey returns false, if gethashcode functions return same output, , if equals method returns true.

what mean? doing wrong here?

additional information

the 2 elements inserting both of type owner, no gethashcode or equals method. these inherit type storable, implements interface, , has gethashcode , equals defined.

here's storable class. wondering if 2 guid properties indeed equal - , yes, are. double-checked. see sample code afterwards.

public abstract class storable : istorable {      public override int gethashcode()     {         return id == default(guid) ? 0 : id.gethashcode();     }      public override bool equals(object obj)     {         var other = obj storable;         return other != null && (other.id == id || referenceequals(obj, this));     }      public guid id { get; set; }      protected storable()     {         id = guid.newguid();     }  } 

now, here's relevant part of code dictionary stuff occurs. takes in supporter object has link owner.

public class chatsession : storable, ichatsession {      static chatsession()     {         pendingsupportsessions = new dictionary<iowner, linkedlist<ichatsession>>();     }      private static readonly idictionary<iowner, linkedlist<ichatsession>> pendingsupportsessions;      public static chatsession assignsupporterfornextpendingsession(isupporter supporter)     {          var owner = supporter.owner;         if (!pendingsupportsessions.containskey(owner)) //always returns false         {             var hashcode1 = owner.gethashcode();             var hashcode2 = pendingsupportsessions.first().key.gethashcode();              var equals = owner.equals(pendingsupportsessions.first().key);              //here, equals true, , 2 hashcodes identical,             //and there 1 element in dictionary according debugger.             //however, calling 2 "add" calls after eachother indeed crash.              pendingsupportsessions.add(owner, new linkedlist<ichatsession>());             pendingsupportsessions.add(owner, new linkedlist<ichatsession>()); //crash         }          ...      }  } 

if need additional information, let me know. not sure kind of information sufficient, hard me include more.

guillaume right. appears changing value of 1 of keys after added dictionary. doh!