Tuples

System.ValueTuple is modern; System.Tuple is legacy.

Tuple

public (string, int) GetFruit() 
{
    return ("Apples", 5)
}

var fruit = GetFruit();

The tuple’s fields are automatically named Item1 and Item2:

fruit.Item1 // returns "Apples"
fruit.Item2 // returns 5

Tuple with Named Fields

public (string Name, int Qty) GetNamedFruit() 
{
    return (Name: "Apples", Qty: 5);
}

var namedFruit = GetNamedFruit();
namedFruit.Name // returns "Apples"
namedFruit.Qty // returns 5

Tuple Deconstruction

(type v1, type v2, …) = function();

… or …

var (v1, v2, …) = function();

… or …

type var1 = val1;
type var2 = val2;
(var1, var2) = function();

Availability: C# 10
It is now possible to assign values to an existing variable and initialize newly declared variables in the same deconstruction:

int x = 0;
(x, int y) = point;

Example

Store return value in a tuple with two named fields:

(string FruitName, int FruitQty) myFruit = GetNamedFruit();
Console.WriteLine(myFruit.FruitName); // output: "Apples"
Console.WriteLine(myFruit.FruitQty); // output: 5

Deconstruct the return value into two separate variables:

(string name, int num) = GetNamedFruit();
Console.WriteLine(name); // output: "Apples"
Console.WriteLine(num); // output: 5