oop - Different kinds of instance of Child- Parent class hierarchy in c# -


i want know relation between instances of parent child in c#.

suppose have 2 classes base , derived:

base b = new base() derived d = new derived() derived db = new base() base bd = new derived()

then meaning of above types of objects

please suggest confused.

assuming base base class of derived....

line 1 contains instance of base class.

line 2 contains instance of derived class.

these both "standard" variables, variable type matches instance contains.

line 4 instance of derived class, restricted accessing base class methods. think of restricted view of derived class.

line 3 should produce compilation error. can't place instance of base class in variable of more restrictive type. think of "all dogs(derived class) animals(base class), not animals dogs.


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