freeCodeCamp/guide/spanish/csharp/linq/first/index.md

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2018-10-12 19:37:13 +00:00
---
title: First
localeTitle: primero
--- # primero
Devuelve el primer elemento que satisface una condición dada opcional. Si no se encuentra ningún elemento, lanza una `InvalidOperationException` ;
### Firma
```csharp
Enumerable.First<TSource>(IEnumerable<TSource>, Func<TSource, Boolean>)
```
## Ejemplo
```csharp
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.First(); // Orange
var firstYellowFruit = fruits.First(f => f.Color == "Yellow"); // Pineapple
```