C# ValueTuple

ValueTuple is a structure introduced in C# 7.0 which represents the value type. Already included in .NET Framework 4.7 or higher version. It allows us to store a data set that contains multiple values that may or may not be related to each other. It can store elements starting from 0 to 8 and can store elements of different types. We can also store duplicate elements in the value tuple.

Need of Value Tuple

We already have Tuples in C# which is used to store multiple values, but have some limitations, these limitations are fixed in ValueTuple. ValueTuple is an improved version of Tuples. It overcomes the following limitations of Tuples:

• Tuple is of reference type, but ValueTuple is of the value type.
• Tuple does not provide naming conventions, but ValueTuple provides strong naming conventions.
• Tuples can't have zero components, but ValueTuple can have zero elements.
• ValueTuple provides a lightweight mechanism for returning multiple values from the existing methods.
• The syntax of ValueTuple is more optimized than Tuples.
• ValueTuple allows flexible element access through deconstruction and the _ keyword, unlike Tuple, which lacks these features.
• In ValueTuple the members such as item1 and item2 are fields. But in Tuple, they are properties.
• In ValueTuple fields are mutable. But in Tuple, fields are read-only.

Creating a ValueTuple

We can create ValueTuples by using the following ways:

• Using Constructor
• Using Create Method
• Using parenthesis()

1. Using Constructor

We can create ValueTuple by using the constructor provided by the ValueTuple<T> Struct, where we can store elements starting from one to eight with their type. 

Syntax:

// Constructor for creating one element

ValueTuple<T1>(T1)

// Constructor for creating two elements

ValueTuple<T1, T2>(T1, T2)

.

.

// Constructor for creating eight elements

ValueTuple<T1, T2, T3, T4, T5, T6, T7, TRest>(T1, T2, T3, T4, T5, T6, T7, TRest)

Example:

first element of ValueTuple: 345678
ValueTuple with three elements: C# Java 586
elements of ValueTuple with eight items: 45 67

2. Using the Create Method

The Create method is a simpler way to create ValueTuple objects without explicitly specifying the types of the tuple elements.

Syntax:

// Method for creating an empty value tuple

Create();

// Method for creating 1-ValueTuple

Create<T1>(T1)

.

.

// Method for creating 8-ValueTuple

Create<T1, T2, T3, T4, T5, T6, T7, TRest>(T1, T2, T3, T4, T5, T6, T7, T8)

Example:

V1 is an empty ValueTuple
V2 Item1: 12
V2 Item3: 40
V3 Item2: GeeksforGeeks
V3 Item6: 56.78

3. Using Parentheses

It is the simplest form for creating ValueTuples using parenthesis "()" and the elements are placed in between them. The elements are stored in 2 different ways:

• Named Member
• UnNamed Member

3.1 Named Member

ValueTuple allows us to create a tuple in which each component is allowed to have a its own name. So we can access that component with the help of their name. It makes the program more readable. We can assign the names to the members on either the left-hand side or right-hand, but not both sides. If we assigned names to both sides, then the left-hand side has precedence over the right-hand side.

Example 1: Named Member

Author's age: 23
Author's name: Geek
Author's language: C#

Example 2: Named Members Using var

Author Name: Geek
Author Age: 23
Author Language: C#

3.2 Unnamed Members

In ValueTuples, the unnamed members are those members who do not have names. They are simply created without any name.

Example:

Author Age: 20
Author Name: Geek
Author Language: C#

Accessing ValueTuple members

1. Accessing UnNamed Members

In ValueTuple, unnamed members are accessible by using the default item property names like Item1, Item2, Item3, etc. As shown in the below example: 

Example:

Age:20
Name:Siya
Language:Ruby

2. Accessing Named Members

In ValueTuples, the named members are used according to their names. There is no need to access these named members with default item property. As shown in the below example, the ValueTuple contains three elements, i.e., Book_id, Author_name, and Book_name. And we directly access these elements according to their names.

Example:

Book Id: 2340
Author Name: Geek
Book Name: C# tutorials

Returning ValueTuple from a Method

In C#, we are allowed to return a ValueTuple from a method. As shown in the below example, the TouristDetails method returns a ValueTuple with 3 elements.

Example: