# Tuple<T1,T2,T3,T4,T5,T6,T7,TRest>.IComparable.CompareTo(Object) Method

## Definition

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.

`` virtual int System.IComparable.CompareTo(System::Object ^ obj) = IComparable::CompareTo;``
``int IComparable.CompareTo (object obj);``
``Function CompareTo (obj As Object) As Integer Implements IComparable.CompareTo``

#### Parameters

obj
Object

An object to compare with the current instance.

#### Returns

A signed integer that indicates the relative position of this instance and `obj` in the sort order, as shown in the following table.

Value Description
A negative integer This instance precedes `obj`.
Zero This instance and `obj` have the same position in the sort order.
A positive integer This instance follows `obj`.

#### Exceptions

`obj` is not a Tuple<T1,T2,T3,T4,T5,T6,T7,TRest> object.

## Examples

The following example creates an array of octuples whose components are integers that contain a range of prime numbers. The example displays the elements of the array in unsorted order, sorts the array, and then displays the array in sorted order. The output shows that the array has been sorted by Item1, or the tuple's first component. Note that the example does not directly call the IComparable.CompareTo(Object) method. This method is called implicitly by the Sort(Array) method for each element in the array.

``````using System;

public class Example
{
public static void Main()
{
// Create array of 8-tuple objects containing prime numbers.
Tuple<Int32, Int32, Int32, Int32, Int32, Int32, Int32, Tuple<Int32>>[] primes =
{ new Tuple<Int32, Int32, Int32, Int32, Int32, Int32, Int32,
Tuple<Int32>>(2, 3, 5, 7, 11, 13, 17, new Tuple<Int32>(19)),
new Tuple<Int32, Int32, Int32, Int32, Int32, Int32, Int32,
Tuple<Int32>>(23, 29, 31, 37, 41, 43, 47, new Tuple<Int32>(55)),
new Tuple<Int32, Int32, Int32, Int32, Int32, Int32, Int32,
Tuple<Int32>>(3, 2, 5, 7, 11, 13, 17, new Tuple<Int32>(19)) };
// Display 8-tuples in unsorted order.
foreach (var prime in primes)
Console.WriteLine(prime.ToString());
Console.WriteLine();

// Sort the array and display its 8-tuples.
Array.Sort(primes);
foreach (var prime in primes)
Console.WriteLine(prime.ToString());
}
}
// The example displays the following output:
//       (2, 3, 5, 7, 11, 13, 17, 19)
//       (23, 29, 31, 37, 41, 43, 47, 55)
//       (3, 2, 5, 7, 11, 13, 17, 19)
//
//       (2, 3, 5, 7, 11, 13, 17, 19)
//       (3, 2, 5, 7, 11, 13, 17, 19)
//       (23, 29, 31, 37, 41, 43, 47, 55)
``````
``````Module Example
Public Sub Main()
' Create array of 8-tuple objects containing prime numbers.
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)),
New Tuple(Of Int32, Int32, Int32, Int32, Int32, Int32, Int32,
Tuple(Of Int32)) (23, 29, 31, 37, 41, 43, 47,
New Tuple(Of Int32)(55)),
New Tuple(Of Int32, Int32, Int32, Int32, Int32, Int32, Int32,
Tuple(Of Int32)) (3, 2, 5, 7, 11, 13, 17,
New Tuple(Of Int32)(19)) }
' Display 8-tuples in unsorted order.
For Each prime In primes
Console.WriteLine(prime.ToString())
Next
Console.WriteLine()

' Sort the array and display its 8-tuples.
Array.Sort(primes)
For Each prime In primes
Console.WriteLine(prime.ToString())
Next
End Sub
End Module
' The example displays the following output:
'       (2, 3, 5, 7, 11, 13, 17, 19)
'       (23, 29, 31, 37, 41, 43, 47, 55)
'       (3, 2, 5, 7, 11, 13, 17, 19)
'
'       (2, 3, 5, 7, 11, 13, 17, 19)
'       (3, 2, 5, 7, 11, 13, 17, 19)
'       (23, 29, 31, 37, 41, 43, 47, 55)
``````

## Remarks

This member is an explicit interface member implementation. It can be used only when the Tuple<T1,T2,T3,T4,T5,T6,T7,TRest> instance is cast to an IComparable interface.

This method provides the IComparable.CompareTo implementation for the Tuple<T1,T2,T3,T4,T5,T6,T7,TRest> class. Although the method can be called directly, it is most commonly called by the default overloads of collection-sorting methods, such as Array.Sort(Array) and SortedList.Add, to order the members of a collection.

Caution

The IComparable.CompareTo method is intended for use in sorting operations. It should not be used when the primary purpose of a comparison is to determine whether two objects are equal. To determine whether two objects are equal, call the Tuple<T1,T2,T3,T4,T5,T6,T7,TRest>.Equals(Object) method.

This method uses the default object comparer to compare each component.