Member lookup over generic constraint in C#? -

i have simple code : (simplified)

 class program     {         static void main(string[] args)         {             var s1 = new student();             var s2 = new student();             mygenericclass<student> mgc = new mygenericclass<student>();             mgc.eq(s1,s2);         }     }      class mygenericclass<t> t : person     {         public void eq(t t1, t t2)         {            console.writeline(t1.equals(t2));         }     }      class person     {          public  bool equals(person p)         {             return true;         }     }      class student : person     {          public bool equals(student obj)         {             return true;         }     } 

the invoked method person's , here question :

the mygenericclass initialized student t student. there constraint there : where t : person - means person should base class. ( , student accomplish this)

question :

1) reason behavior relates generics ?

2) if , why still person's method running , not student ? stopping dealing student ?

edit , saw in spec

if "this behavior" mean calls method on person, no, normal oop.

in order code call "the correct" method depending on actual t used, need make method virtual in base class, , override in descendants:

class person {     public virtual bool equals(person p)     {         return true;     } }  class student : person {     public override bool equals(person obj)     {         return true;     } } 

but observe else well, in order equals in student override 1 in person, needs take person parameter well.

note generics doesn't mean "figure out method call @ runtime", it's still compiler determines, @ compile-time, methods call, , can see when compiling generic class person class, cannot determine potential usage of student.

you can verify behavior simple linqpad program:

void main() {     base o = new derived();     o.test1();     o.test2(); }  public class base {     public void test1()     {         debug.writeline("base.test1");     }      public virtual void test2()     {         debug.writeline("base.test2");     } }  public class derived : base {     public void test1()     {         debug.writeline("derived.test1");     }      public override void test2()     {         debug.writeline("derived.test2");     } } 

output:

base.test1 derived.test2 

as warning (which have in code well):

warning: 'userquery.derived.test1()' hides inherited member 'userquery.base.test1()'. use new keyword if hiding intended.