freeCodeCamp/guide/english/csharp/linq/first-or-default/index.md

1019 B
Raw Blame History

title
First Or Default

FirstOrDefault

Returns the first element that satisfies an optional given condition. If no element is found, the default() of the object is returned

Signature

Enumerable.FirstOrDefault<TSource>(IEnumerable<TSource>,Func<TSource,Boolean>)

Example

var fruits = new List<Fruit>() {
    new Fruit() { Id = 1, Name = "Orange",     Color = "Orange", Quantity: 3   },
    new Fruit() { Id = 2, Name = "Strawberry", Color = "Red",    Quantity: 12  },
    new Fruit() { Id = 3, Name = "Grape",      Color = "Purple", Quantity: 25  },
    new Fruit() { Id = 4, Name = "Pineapple",  Color = "Yellow", Quantity: 1   },
    new Fruit() { Id = 5, Name = "Apple",      Color = "Red",    Quantity: 5   },
    new Fruit() { Id = 6, Name = "Mango",      Color = "Yellow", Quantity: 2   }
};

var firstFruit = fruits.FirstOrDefault(); // Orange

var firstYellowFruit = fruits.FirstOrDefault(f => f.Color == "Green"); // null