แก้ไข

แชร์ผ่าน


Tuple<T1>.IComparable.CompareTo(Object) Method

Definition

Compares the current Tuple<T1> 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 -> int
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.

Implements

Exceptions

obj is not a Tuple<T1> object.

Examples

The following example creates an array of singletons whose component is a Double value. It displays the value of each tuple component in unsorted order, sorts the array, and then displays the values in sorted order. Note that the example does not directly call the Tuple<T1>.IComparable.CompareTo method. This method is called implicitly by the Sort(Array) method for each element in the array.

using System;

class Example
{
   static void Main()
   {
      Tuple<Double>[] values = { Tuple.Create(13.54),
                                 Tuple.Create(Double.NaN),
                                 Tuple.Create(-189.42993),
                                 Tuple.Create(Double.PositiveInfinity),
                                 Tuple.Create(Double.Epsilon),
                                 Tuple.Create(1.934E-17),
                                 Tuple.Create(Double.NegativeInfinity),
                                 Tuple.Create(-0.000000000003588),
                                 null };
      Console.WriteLine("The values in unsorted order:");
      foreach (var value in values)
         if (value != null)
            Console.WriteLine("   {0}", value.Item1);
         else
            Console.WriteLine("   <null>");
      Console.WriteLine();

      Array.Sort(values);

      Console.WriteLine("The values in sorted order:");
      foreach (var value in values)
         if (value != null)
            Console.WriteLine("   {0}", value.Item1);
         else
            Console.WriteLine("   <null>");
   }
}
// The example displays the following output:
//      The values in unsorted order:
//         13.54
//         NaN
//         -189.42993
//         Infinity
//         4.94065645841247E-324
//         1.934E-17
//         -Infinity
//         -3.588E-12
//
//      The values in sorted order:
//         NaN
//         -Infinity
//         -189.42993
//         -3.588E-12
//         4.94065645841247E-324
//         1.934E-17
//         13.54
//         Infinity
open System

let values = 
    [| Tuple.Create 13.54
       Tuple.Create Double.NaN
       Tuple.Create -189.42993
       Tuple.Create Double.PositiveInfinity
       Tuple.Create Double.Epsilon
       Tuple.Create 1.934E-17
       Tuple.Create Double.NegativeInfinity
       Tuple.Create -0.000000000003588
       null |]
printfn "The values in unsorted order:"
for value in values do
    printfn $"   %A{value.Item1}"
printfn ""

Array.Sort values

printfn "The values sorted in descending order:"
for value in values do
    printfn $"   %A{value.Item1}"
// The example displays the following output:
//      The values in unsorted order:
//         13.54
//         NaN
//         -189.42993
//         Infinity
//         4.94065645841247E-324
//         1.934E-17
//         -Infinity
//         -3.588E-12
//
//      The values in sorted order:
//         NaN
//         -Infinity
//         -189.42993
//         -3.588E-12
//         4.94065645841247E-324
//         1.934E-17
//         13.54
//         Infinity
Module Example
    Sub Main()
        Dim values() = { Tuple.Create(13.54),
                         Tuple.Create(Double.NaN),
                         Tuple.Create(-189.42993),
                         Tuple.Create(Double.PositiveInfinity),
                         Tuple.Create(Double.Epsilon),
                         Tuple.Create(1.934E-17),
                         Tuple.Create(Double.NegativeInfinity),
                         Tuple.Create(-0.000000000003588),
                         Nothing}

        Console.WriteLine("The values in unsorted order:")
        For Each value In values
            If value IsNot Nothing Then
                Console.WriteLine("   {0}", value.Item1)
            Else
                Console.WriteLine("   <null>")
            End If
        Next
        Console.WriteLine()

        Array.Sort(values)

        Console.WriteLine("The values in sorted order:")
        For Each value In values
            If value IsNot Nothing Then
                Console.WriteLine("   {0}", value.Item1)
            Else
                Console.WriteLine("   <null>")
            End If
        Next
    End Sub
End Module
' The example displays the following output:
'      The values in unsorted order:
'         13.54
'         NaN
'         -189.42993
'         Infinity
'         4.94065645841247E-324
'         1.934E-17
'         -Infinity
'         -3.588E-12
'
'      The values in sorted order:
'         NaN
'         -Infinity
'         -189.42993
'         -3.588E-12
'         4.94065645841247E-324
'         1.934E-17
'         13.54
'         Infinity

Remarks

This member is an explicit interface member implementation. It can be used only when the Tuple<T1> instance is cast to an IComparable interface.

This method provides the IComparable.CompareTo implementation for the Tuple<T1> 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>.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>.IComparable.CompareTo method uses the default object comparer.

Applies to

See also