How to create 2-tuple or pair tuple in C#?

The Tuple<T1, T2> class in C# represents a 2-tuple, also known as a pair. A tuple is a data structure that contains a sequence of elements of different types. The 2-tuple holds exactly two values that can be accessed using Item1 and Item2 properties.

2-tuples are useful when you need to return two values from a method or group two related values together without creating a separate class.

Syntax

Following is the syntax for creating a 2-tuple −

Tuple<T1, T2> tuple = new Tuple<T1, T2>(value1, value2);

Accessing tuple elements −

var firstValue = tuple.Item1;
var secondValue = tuple.Item2;

Using String Pair Tuple

This example demonstrates creating a 2-tuple with two string values −

using System;

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

The output of the above code is −

First Value = jack
Second Value = steve
Found: First tuple value = jack
Found: Second tuple value = steve

Using Mixed Type Tuple

This example shows a 2-tuple with different data types (integer and string) −

using System;

public class Demo {
   public static void Main(string[] args) {
      Tuple<int, string> tuple = new Tuple<int, string>(20, "steve");
      Console.WriteLine("Integer Value = " + tuple.Item1);
      Console.WriteLine("String Value = " + tuple.Item2);
      
      if (tuple.Item1 == 20) {
         Console.WriteLine("Found: Integer value = " + tuple.Item1);
      }
      if (tuple.Item2 == "steve") {
         Console.WriteLine("Found: String value = " + tuple.Item2);
      }
   }
}

The output of the above code is −

Integer Value = 20
String Value = steve
Found: Integer value = 20
Found: String value = steve

Using Tuple.Create Method

C# provides a more convenient way to create tuples using the Tuple.Create method −

using System;

public class Demo {
   public static void Main(string[] args) {
      var studentInfo = Tuple.Create("Alice", 85);
      var coordinates = Tuple.Create(10.5, 20.3);
      
      Console.WriteLine("Student: " + studentInfo.Item1 + ", Score: " + studentInfo.Item2);
      Console.WriteLine("X: " + coordinates.Item1 + ", Y: " + coordinates.Item2);
      
      // Tuple comparison
      var point1 = Tuple.Create(5, 10);
      var point2 = Tuple.Create(5, 10);
      
      Console.WriteLine("Points are equal: " + point1.Equals(point2));
   }
}

The output of the above code is −

Student: Alice, Score: 85
X: 10.5, Y: 20.3
Points are equal: True

Conclusion

2-tuples in C# provide a simple way to group two related values of different types without creating a custom class. They are particularly useful for returning multiple values from methods or temporarily pairing data. Use Tuple.Create for more concise syntax and cleaner code.