C# Best way to compare fields of class -

i need have possibility of comparison of product, advancedproduct (and other classes inherit class product) how better realize hierarchical check of fields? example, want check 2 advancedproduct classes, first check fields basic class product check additional fields of advancedproduct , return in form (???) changes between them (maybe class pchanges???). whether there suitable template? how make this, make rather flexibly subsequent use?

        public class product     {         public string id;         public string name;          public product(string id, string name)         {             this.id = id;             this.name = name;         }       }      public class advancedproduct : product     {         public string currentversion;          public advancedproduct(string id, string name, string version)             : base(id, name) { }     }      public class pchanges     {         public bool namechanged = false;         public bool versionchanged = false;          public pchanges() { }      }      public class productcomparer     {         pchanges changes = new pchanges();          public productcomparer() { }          public pchanges compare(advancedproduct p1, advancedproduct p2)         {             if (p1.name != p2.name)                 changes.namechanged = true;             if (p1.currentversion != p2.currentversion)                 changes.versionchanged = true;              return changes;          }     } 

based on uzzy's answer, looks can extended track change. bad practice, yes, small app should enough. example:

public class productcomparer : iequalitycomparer<product>{     private pchanges change;     public pchanges changes{ { return change; } }      public bool equals(product p1, product p2){         pchanges newchange = new pchanges();         bool equal = true;         if(p1.name != p2.name){             newchange.namechange = true;             equal = false;         }         this.change = newchange;         return equal;     } } 

edit:

i misread requirement of extendable field comparison. if case, decorator pattern best you. assuming every other product class should inherited product class.

public class productcomparer{     public virtual void trackchange(product p1, product p2, ref pchange change){         if(p1.name != p2.name){             change.namechange = true;         }         // other base validation     } }  public class advancedproductcomparer : productcomparer{     public advancedproductcomparer(productcomparer basecomparer){         this.basecomparer = basecomparer;     }     productcomparer basecomparer;      public override void trackchange(product p1, product p2, ref pchange change){         basecomparer.compare(p1, p2, ref change);         if( ((advancedproduct)p1).currentversion != ((advancedproduct)p2).currentversion){             change.currentversion = true;         }     } }  public class productcomparerservice{     public productcomparerservice(productcomparer comparer){         this.comparer = comparer;     }      productcomparer comparer;     private pchanges change;     public pchanges changes{ { return change; } }      public bool equals(product p1, product p2){         pchanges newchange = new pchanges();         comparer.compare(p1,p2, ref newchange);                      this.change = newchange;         return (newchange.currentversion || newchange.namechange);     }  } 

the usage:

productcomparer pcompare = new productcomparer(); advancedproductcomparer advcompare = new advancedproductcomparer(pcompare); productcomparerservice service = new productcomparerservice(advcompare); if( service.equals(p1,p2) ){     pchange change = service.change; }