c# - FirstOrDefault on collection of objects -

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i have following classes:

public class animal {     ... }  public class cow : animal {     ... }  public class animalcollection : list<animal> {     public animal getfirstanimal<t>()     {         foreach(animal animal in this)         {             if(animal t)                 return t animal         }          return null;     } }

a few questions: possible use firstordefault on collection instead of having getfirstanimal() method? syntax if can? efficient? isn't going massive collection.

alternatively, there better way of doing same thing together?

var firstcow = animals.oftype<cow>().firstordefault();

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