Article
11/17/2011

Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> Class

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Represents an n-tuple, where n is 8 or greater.

Inheritance Hierarchy

System.Object
System.Tuple<T1, T2, T3, T4, T5, T6, T7, TRest>

Namespace: System
Assembly: mscorlib (in mscorlib.dll)

Syntax

'Declaration
Public Class Tuple(Of T1, T2, T3, T4, T5, T6, T7, TRest) _
    Implements IStructuralEquatable, IStructuralComparable, IComparable

public class Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> : IStructuralEquatable, 
    IStructuralComparable, IComparable

Type Parameters

T1
The type of the tuple's first component.

T2
The type of the tuple's second component.

T3
The type of the tuple's third component.

T4
The type of the tuple's fourth component.

T5
The type of the tuple's fifth component.

T6
The type of the tuple's sixth component.

T7
The type of the tuple's seventh component.

TRest
Any generic Tuple object that defines the types of the tuple's remaining components.

The Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> type exposes the following members.

Constructors

	Name	Description
	Tuple<T1, T2, T3, T4, T5, T6, T7, TRest>	Initializes a new instance of the Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> class.

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Properties

	Name	Description
	Item1	Gets the value of the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object's first component.
	Item2	Gets the value of the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object's second component.
	Item3	Gets the value of the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object's third component.
	Item4	Gets the value of the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object's fourth component.
	Item5	Gets the value of the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object's fifth component.
	Item6	Gets the value of the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object's sixth component.
	Item7	Gets the value of the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object's seventh component.
	Rest	Gets the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object's remaining components.

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Methods

	Name	Description
	Equals	Returns a value that indicates whether the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object is equal to a specified object. (Overrides Object.Equals(Object).)
	Finalize	Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
	GetHashCode	Calculates the hash code for the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object. (Overrides Object.GetHashCode().)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	ToString	Returns a string that represents the value of this Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> instance. (Overrides Object.ToString().)

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Explicit Interface Implementations

	Name	Description
	IComparable.CompareTo	Compares the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object to a specified object and returns an integer that indicates whether the current object is before, after, or in the same position as the specified object in the sort order.
	IStructuralComparable.CompareTo	Compares the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object to a specified object by using a specified comparer and returns an integer that indicates whether the current object is before, after, or in the same position as the specified object in the sort order.
	IStructuralEquatable.Equals	Returns a value that indicates whether the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object is equal to a specified object based on a specified comparison method.
	IStructuralEquatable.GetHashCode	Calculates the hash code for the current Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object by using a specified computation method.

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Remarks

A tuple is a data structure that has a specific number and sequence of values. The Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> class represents an n-tuple that has eight or more components.

You can instantiate a Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object with exactly eight components by calling the static Tuple.Create method. The following example creates an 8-tuple (octuple) that contains prime numbers that are less than 20. Note that it uses type inference to determine the type of each component.

Dim primes = Tuple.Create(2, 3, 5, 7, 11, 13, 17, 19)

var primes = Tuple.Create(2, 3, 5, 7, 11, 13, 17, 19);

You can also instantiate an n-tuple object with eight or more components by calling the Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> constructor. The following example uses the Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> constructor to create an 8-tuple that is equivalent to the tuple created in the previous example.

Dim primes = New Tuple(Of Int32, Int32, Int32, Int32, Int32, Int32, Int32,  _
             Tuple(Of Int32))(2, 3, 5, 7, 11, 13, 17, New Tuple(Of Int32)(19))

var primes = new Tuple<Int32, Int32, Int32, Int32, Int32, Int32, Int32,
             Tuple<Int32>>(2, 3, 5, 7, 11, 13, 17, new Tuple<Int32>(19));

Note:
To create an n-tuple with nine or more components, you must call the Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> constructor. The static factory methods of the Tuple class do not support the creation of Tuple objects with more than eight components.

To instantiate an n-tuple that has eight or more components with the Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> constructor, you supply a generic Tuple object as the rest parameter to define the eighth through nth components of the tuple. By nesting generic Tuple objects in this way, you can create a tuple that has no practical limitation on the number of its components.

The following example creates a 17-tuple that contains population data for the city of Detroit, Michigan, for each national census from 1860 to 2000. The first component of the tuple is the city name. The second component is the start date of the data series, and the third component is the population at the start date. Each subsequent component provides the population at decade intervals. The 17-tuple is created by nesting a Tuple<T1, T2, T3> object inside a Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object. (That is, the Tuple<T1, T2, T3> object is supplied as the value of the rest parameter in the Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> class constructor.) This Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object is, in turn, nested in an outer Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object. (That is, the Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object is supplied as the value of the rest parameter in the outer Tuple<T1, T2, T3, T4, T5, T6, T7, TRest> object's class constructor.)

outputBlock.FontFamily = New System.Windows.Media.FontFamily("Courier New")

Dim from1980 = Tuple.Create(1203339, 1027974, 951270)
Dim from1910 As New Tuple(Of Integer, Integer, Integer, Integer, Integer, Integer, Integer,  _
    Tuple(Of Integer, Integer, Integer)) _
    (465766, 993078, 1568622, 1623452, 1849568, 1670144, 1511462, from1980)
Dim population As New Tuple(Of String, Integer, Integer, Integer, Integer, Integer, Integer,  _
    Tuple(Of Integer, Integer, Integer, Integer, Integer, Integer, Integer, Tuple(Of Integer, Integer, Integer))) _
    ("Detroit", 1860, 45619, 79577, 116340, 205876, 285704, from1910)

outputBlock.FontFamily = new System.Windows.Media.FontFamily("Courier New");

var from1980 = Tuple.Create(1203339, 1027974, 951270);
var from1910 = new Tuple<int, int, int, int, int, int, int, Tuple<int, int, int>>
    (465766, 993078, 1568622, 1623452, 1849568, 1670144, 1511462, from1980);
var population = new Tuple<string, int, int, int, int, int, int,
    Tuple<int, int, int, int, int, int, int, Tuple<int, int, int>>>
    ("Detroit", 1860, 45619, 79577, 116340, 205876, 285704, from1910);

You can retrieve the value of the tuple's first seven components by using the read-only Item1, Item2, Item3, Item4, Item5, Item6, and Item7 instance properties. Any additional components are nested and can be retrieved from the Rest property. In the previous example, the Item1 through Item7 properties retrieve the first through seventh components of the tuple. The eighth through fourteenth components are contained in the tuple that is nested at the second level, and are represented by the Rest.Item1 through Rest.Item7 properties. The fifteenth through seventeenth components are contained in the tuple that is nested at the third level, and are represented by the Rest.Rest.Item1 though Rest.Rest.Item3 properties.

Tuples are commonly used in four different ways:

To represent a single set of data. For example, a tuple can represent a database record, and its components can represent individual fields of the record.
To provide easy access to, and manipulation of, a data set.
To return multiple values from a method without the use of out parameters (in C#) or ByRef parameters (in Visual Basic). For example, the previous example returns its computed statistics, along with the city name, in a Tuple<T1, T2, T3, T4, T5, T6, T7> object.
To pass multiple values to a method through a single parameter. For example, the Thread.Start(Object) method has a single parameter that lets you supply one value to the method that the thread executes at startup. If you supply a Tuple<T1, T2, T3, T4, T5, T6, T7> object as the method argument, you can supply the thread’s startup routine with seven items of data.

Version Information

Silverlight

Supported in: 5, 4

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.