Tuple<T1,T2>.IComparable.CompareTo(Object) Method
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Compares the current Tuple<T1,T2> 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);abstract member System.IComparable.CompareTo : obj -> int
override this.System.IComparable.CompareTo : obj -> intFunction CompareTo (obj As Object) As Integer Implements IComparable.CompareToParameters
- 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.
|
Implements
Exceptions
obj is not a Tuple<T1,T2> object.
Examples
The following example creates an array of Tuple<T1,T2> objects that consist of a student's name and test score. It displays the component of each tuple in the array in unsorted order, sorts the array, and then calls ToString to display the value of each tuple in sorted order. The output shows that the array has been sorted by its 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()
{
Tuple<string, Nullable<int>>[] scores =
{ new Tuple<string, Nullable<int>>("Jack", 78),
new Tuple<string, Nullable<int>>("Abbey", 92),
new Tuple<string, Nullable<int>>("Dave", 88),
new Tuple<string, Nullable<int>>("Sam", 91),
new Tuple<string, Nullable<int>>("Ed", null),
new Tuple<string, Nullable<int>>("Penelope", 82),
new Tuple<string, Nullable<int>>("Linda", 99),
new Tuple<string, Nullable<int>>("Judith", 84) };
Console.WriteLine("The values in unsorted order:");
foreach (Tuple<string, Nullable<int>> score in scores)
Console.WriteLine(score.ToString());
Console.WriteLine();
Array.Sort(scores);
Console.WriteLine("The values in sorted order:");
foreach (Tuple<string, Nullable<int>> score in scores)
Console.WriteLine(score.ToString());
}
}
// The example displays the following output;
// The values in unsorted order:
// (Jack, 78)
// (Abbey, 92)
// (Dave, 88)
// (Sam, 91)
// (Ed, )
// (Penelope, 82)
// (Linda, 99)
// (Judith, 84)
//
// The values in sorted order:
// (Abbey, 92)
// (Dave, 88)
// (Ed, )
// (Jack, 78)
// (Judith, 84)
// (Linda, 99)
// (Penelope, 82)
// (Sam, 91)
open System
let scores =
[| Tuple<string, Nullable<int>>("Jack", 78)
Tuple<string, Nullable<int>>("Abbey", 92)
Tuple<string, Nullable<int>>("Dave", 88)
Tuple<string, Nullable<int>>("Sam", 91)
Tuple<string, Nullable<int>>("Ed", Nullable())
Tuple<string, Nullable<int>>("Penelope", 82)
Tuple<string, Nullable<int>>("Linda", 99)
Tuple<string, Nullable<int>>("Judith", 84) |]
printfn "The values in unsorted order:"
for score in scores do
printfn $"{score}"
printfn ""
Array.Sort scores
printfn "The values in sorted order:"
for score in scores do
printfn $"{score}"
// The example displays the following output
// The values in unsorted order:
// (Jack, 78)
// (Abbey, 92)
// (Dave, 88)
// (Sam, 91)
// (Ed, )
// (Penelope, 82)
// (Linda, 99)
// (Judith, 84)
//
// The values in sorted order:
// (Abbey, 92)
// (Dave, 88)
// (Ed, )
// (Jack, 78)
// (Judith, 84)
// (Linda, 99)
// (Penelope, 82)
// (Sam, 91)
Module Example
Public Sub Main()
Dim scores() As Tuple(Of String, Nullable(Of Integer)) =
{ New Tuple(Of String, Nullable(Of Integer))("Jack", 78),
New Tuple(Of String, Nullable(Of Integer))("Abbey", 92),
New Tuple(Of String, Nullable(Of Integer))("Dave", 88),
New Tuple(Of String, Nullable(Of Integer))("Sam", 91),
New Tuple(Of String, Nullable(Of Integer))("Ed", Nothing),
New Tuple(Of String, Nullable(Of Integer))("Penelope", 82),
New Tuple(Of String, Nullable(Of Integer))("Linda", 99),
New Tuple(Of String, Nullable(Of Integer))("Judith", 84) }
Console.WriteLine("The values in unsorted order:")
For Each score In scores
Console.WriteLine(score.ToString())
Next
Console.WriteLine()
Array.Sort(scores)
Console.WriteLine("The values in sorted order:")
For Each score In scores
Console.WriteLine(score.ToString())
Next
End Sub
End Module
' The example displays the following output;
' The values in unsorted order:
' (Jack, 78)
' (Abbey, 92)
' (Dave, 88)
' (Sam, 91)
' (Ed, )
' (Penelope, 82)
' (Linda, 99)
' (Judith, 84)
'
' The values in sorted order:
' (Abbey, 92)
' (Dave, 88)
' (Ed, )
' (Jack, 78)
' (Judith, 84)
' (Linda, 99)
' (Penelope, 82)
' (Sam, 91)
Remarks
This member is an explicit interface member implementation. It can be used only when the Tuple<T1,T2> instance is cast to an IComparable interface.
This method provides the IComparable.CompareTo implementation for the Tuple<T1,T2> 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 Tuple<T1,T2>.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 Equals method.
The Tuple<T1,T2>.IComparable.CompareTo method uses the default object comparer to compare each component.
