How to create 3-Tuple or Triple Tuple in C#?

The Tuple<T1, T2, T3> class represents a 3-tuple, also called a triple. A tuple is a data structure that contains a sequence of elements of different types, providing a convenient way to group related data together without creating a custom class.

3-tuples are commonly used for −

• Easier access to a data set with three related values.

• Easier manipulation of grouped data.

• To represent a single set of three related values.

• To return multiple values from a method.

• To pass multiple values to a method as a single parameter.

Syntax

Following is the syntax for creating a 3-tuple −

Tuple<T1, T2, T3> tuple = new Tuple<T1, T2, T3>(item1, item2, item3);

Accessing tuple elements −

tuple.Item1  // First element
tuple.Item2  // Second element
tuple.Item3  // Third element

Using Mixed Data Types

A 3-tuple can store different data types in each position −

using System;

public class Demo {
    public static void Main(string[] args) {
        Tuple<int, string, string> tuple = new Tuple<int, string, string>(35, "steve", "katie");
        
        Console.WriteLine("Value (Item1)= " + tuple.Item1);
        Console.WriteLine("Value (Item2)= " + tuple.Item2);
        Console.WriteLine("Value (Item3)= " + tuple.Item3);
        
        if (tuple.Item1 == 35) {
            Console.WriteLine("Exists: Tuple Value = " + tuple.Item1);
        }
        if (tuple.Item2 == "jack") {
            Console.WriteLine("Exists: Tuple Value = " + tuple.Item2);
        }
        if (tuple.Item3 == "katie") {
            Console.WriteLine("Exists: Tuple Value = " + tuple.Item3);
        }
    }
}

The output of the above code is −

Value (Item1)= 35
Value (Item2)= steve
Value (Item3)= katie
Exists: Tuple Value = 35
Exists: Tuple Value = katie

Using Same Data Types

All three elements in a tuple can also be of the same type −

using System;

public class Demo {
    public static void Main(string[] args) {
        Tuple<string, string, string> tuple = new Tuple<string, string, string>("nathan", "steve", "katie");
        
        Console.WriteLine("Value (Item1)= " + tuple.Item1);
        Console.WriteLine("Value (Item2)= " + tuple.Item2);
        Console.WriteLine("Value (Item3)= " + tuple.Item3);
        
        if (tuple.Item1 == "nathan") {
            Console.WriteLine("Exists: Tuple Value = " + tuple.Item1);
        }
        if (tuple.Item2 == "jack") {
            Console.WriteLine("Exists: Tuple Value = " + tuple.Item2);
        }
        if (tuple.Item3 == "katie") {
            Console.WriteLine("Exists: Tuple Value = " + tuple.Item3);
        }
    }
}

The output of the above code is −

Value (Item1)= nathan
Value (Item2)= steve
Value (Item3)= katie
Exists: Tuple Value = nathan
Exists: Tuple Value = katie

Using Tuple.Create Method

You can also create a 3-tuple using the Tuple.Create method, which infers the types automatically −

using System;

public class Demo {
    public static void Main(string[] args) {
        var coordinates = Tuple.Create(10.5, 20.3, 15.7);
        
        Console.WriteLine("X coordinate: " + coordinates.Item1);
        Console.WriteLine("Y coordinate: " + coordinates.Item2);
        Console.WriteLine("Z coordinate: " + coordinates.Item3);
        Console.WriteLine("Type: " + coordinates.GetType());
    }
}

The output of the above code is −

X coordinate: 10.5
Y coordinate: 20.3
Z coordinate: 15.7
Type: System.Tuple`3[System.Double,System.Double,System.Double]

Conclusion

The 3-tuple in C# provides a simple way to group three related values of any type without creating a custom class. You can create tuples using the constructor or the Tuple.Create method, and access elements using Item1, Item2, and Item3 properties.