IComparable<T> IComparable<T> IComparable<T> IComparable<T> Interface

정의

인스턴스를 정렬하는 형식 고유의 비교 메서드를 만들기 위해 값 형식 또는 클래스에서 구현하는 일반화된 비교 메서드를 정의합니다.Defines a generalized comparison method that a value type or class implements to create a type-specific comparison method for ordering or sorting its instances.

generic <typename T>
public interface class IComparable
public interface IComparable<in T>
type IComparable<'T> = interface
Public Interface IComparable(Of In T)

형식 매개 변수

T

비교할 개체의 형식입니다.The type of object to compare.

파생

예제

다음 예제에서는 간단한 IComparable<T> Temperature 개체에 대 한의 구현을 보여 줍니다.The following example illustrates the implementation of IComparable<T> for a simple Temperature object. 이 예에서는 만듭니다는 SortedList<TKey,TValue> 사용 하 여 문자열의 컬렉션 Temperature 키 개체와 여러 쌍의 온도 문자열 순서 목록에 추가 합니다.The example creates a SortedList<TKey,TValue> collection of strings with Temperature object keys, and adds several pairs of temperatures and strings to the list out of sequence. 호출에는 Add 메서드를를 SortedList<TKey,TValue> 컬렉션 사용은 IComparable<T> 온도 증가 하는 순서에 표시 되는 목록 항목을 정렬 하려면 구현 합니다.In the call to the Add method, the SortedList<TKey,TValue> collection uses the IComparable<T> implementation to sort the list entries, which are then displayed in order of increasing temperature.

#using <System.dll>

using namespace System;
using namespace System::Collections::Generic;

public ref class Temperature: public IComparable<Temperature^> {

protected:
   // The underlying temperature value.
   Double m_value;

public:
   // Implement the generic CompareTo method with the Temperature class 
   // as the Type parameter. 
   virtual Int32 CompareTo( Temperature^ other ) {
   
      // If other is not a valid object reference, this instance 
      // is greater.
      if (other == nullptr) return 1;
      
      // The temperature comparison depends on the comparison of the
      // the underlying Double values. 
      return m_value.CompareTo( other->m_value );
   }

       // Define the is greater than operator.
    bool operator>=  (Temperature^ other)
    {
       return CompareTo(other) == 1;
    }
    
    // Define the is less than operator.
    bool operator<  (Temperature^ other)
    {
       return CompareTo(other) == -1;
    }
    
       // Define the is greater than or equal to operator.
    bool operator>  (Temperature^ other)
    {
       return CompareTo(other) >= 0;
    }
    
    // Define the is less than or equal to operator.
    bool operator<=  (Temperature^ other)
    {
       return CompareTo(other) <= 0;
    }

   property Double Celsius {
      Double get() {
         return m_value + 273.15;
      }
   }

   property Double Kelvin {
      Double get() {
         return m_value;
      }
      void set( Double value ) {
         if (value < 0)
            throw gcnew ArgumentException("Temperature cannot be less than absolute zero.");
         else
            m_value = value;
      }
   }

   Temperature(Double kelvins) {
      this->Kelvin = kelvins;
   }
};

int main() {
   SortedList<Temperature^, String^>^ temps = 
      gcnew SortedList<Temperature^, String^>();

   // Add entries to the sorted list, out of order.
   temps->Add(gcnew Temperature(2017.15), "Boiling point of Lead");
   temps->Add(gcnew Temperature(0), "Absolute zero");
   temps->Add(gcnew Temperature(273.15), "Freezing point of water");
   temps->Add(gcnew Temperature(5100.15), "Boiling point of Carbon");
   temps->Add(gcnew Temperature(373.15), "Boiling point of water");
   temps->Add(gcnew Temperature(600.65), "Melting point of Lead");

   for each( KeyValuePair<Temperature^, String^>^ kvp in temps )
   {
      Console::WriteLine("{0} is {1} degrees Celsius.", kvp->Value, kvp->Key->Celsius);
   }
}
/* The example displays the following output:
      Absolute zero is 273.15 degrees Celsius.
      Freezing point of water is 546.3 degrees Celsius.
      Boiling point of water is 646.3 degrees Celsius.
      Melting point of Lead is 873.8 degrees Celsius.
      Boiling point of Lead is 2290.3 degrees Celsius.
      Boiling point of Carbon is 5373.3 degrees Celsius.
*/
using System;
using System.Collections.Generic;

public class Temperature : IComparable<Temperature>
{
    // Implement the generic CompareTo method with the Temperature 
    // class as the Type parameter. 
    //
    public int CompareTo(Temperature other)
    {
        // If other is not a valid object reference, this instance is greater.
        if (other == null) return 1;
        
        // The temperature comparison depends on the comparison of 
        // the underlying Double values. 
        return m_value.CompareTo(other.m_value);
    }

    // Define the is greater than operator.
    public static bool operator >  (Temperature operand1, Temperature operand2)
    {
       return operand1.CompareTo(operand2) == 1;
    }
    
    // Define the is less than operator.
    public static bool operator <  (Temperature operand1, Temperature operand2)
    {
       return operand1.CompareTo(operand2) == -1;
    }

    // Define the is greater than or equal to operator.
    public static bool operator >=  (Temperature operand1, Temperature operand2)
    {
       return operand1.CompareTo(operand2) >= 0;
    }
    
    // Define the is less than or equal to operator.
    public static bool operator <=  (Temperature operand1, Temperature operand2)
    {
       return operand1.CompareTo(operand2) <= 0;
    }

    // The underlying temperature value.
    protected double m_value = 0.0;

    public double Celsius    
    {
        get
        {
            return m_value - 273.15;
        }
    }

    public double Kelvin    
    {
        get
        {
            return m_value;
        }
        set
        {
            if (value < 0.0)
            {
                throw new ArgumentException("Temperature cannot be less than absolute zero.");
            }
            else
            {
                m_value = value;
            }
        }
    }

    public Temperature(double kelvins)
    {
        this.Kelvin = kelvins;
    }
}

public class Example
{
    public static void Main()
    {
        SortedList<Temperature, string> temps = 
            new SortedList<Temperature, string>();

        // Add entries to the sorted list, out of order.
        temps.Add(new Temperature(2017.15), "Boiling point of Lead");
        temps.Add(new Temperature(0), "Absolute zero");
        temps.Add(new Temperature(273.15), "Freezing point of water");
        temps.Add(new Temperature(5100.15), "Boiling point of Carbon");
        temps.Add(new Temperature(373.15), "Boiling point of water");
        temps.Add(new Temperature(600.65), "Melting point of Lead");

        foreach( KeyValuePair<Temperature, string> kvp in temps )
        {
            Console.WriteLine("{0} is {1} degrees Celsius.", kvp.Value, kvp.Key.Celsius);
        }
    }
}
/* This example displays the following output:
      Absolute zero is -273.15 degrees Celsius.
      Freezing point of water is 0 degrees Celsius.
      Boiling point of water is 100 degrees Celsius.
      Melting point of Lead is 327.5 degrees Celsius.
      Boiling point of Lead is 1744 degrees Celsius.
      Boiling point of Carbon is 4827 degrees Celsius.
*/
Imports System.Collections.Generic

Public Class Temperature
    Implements IComparable(Of Temperature)

    ' Implement the generic CompareTo method with the Temperature class 
    ' as the type parameter. 
    '
    Public Overloads Function CompareTo(ByVal other As Temperature) As Integer _
        Implements IComparable(Of Temperature).CompareTo

        ' If other is not a valid object reference, this instance is greater.
        If other Is Nothing Then Return 1
        
        ' The temperature comparison depends on the comparison of the
        ' the underlying Double values. 
        Return m_value.CompareTo(other.m_value)
    End Function
    
    ' Define the is greater than operator.
    Public Shared Operator >  (operand1 As Temperature, operand2 As Temperature) As Boolean
       Return operand1.CompareTo(operand2) = 1
    End Operator
    
    ' Define the is less than operator.
    Public Shared Operator <  (operand1 As Temperature, operand2 As Temperature) As Boolean
       Return operand1.CompareTo(operand2) = -1
    End Operator

    ' Define the is greater than or equal to operator.
    Public Shared Operator >=  (operand1 As Temperature, operand2 As Temperature) As Boolean
       Return operand1.CompareTo(operand2) >= 0
    End Operator
    
    ' Define the is less than operator.
    Public Shared Operator <=  (operand1 As Temperature, operand2 As Temperature) As Boolean
       Return operand1.CompareTo(operand2) <= 0
    End Operator

    ' The underlying temperature value.
    Protected m_value As Double = 0.0

    Public ReadOnly Property Celsius() As Double
        Get
            Return m_value - 273.15
        End Get
    End Property

    Public Property Kelvin() As Double
        Get
            Return m_value
        End Get
        Set(ByVal Value As Double)
            If value < 0.0 Then 
                Throw New ArgumentException("Temperature cannot be less than absolute zero.")
            Else
                m_value = Value
            End If
        End Set
    End Property

    Public Sub New(ByVal kelvins As Double)
        Me.Kelvin = kelvins 
    End Sub
End Class

Public Class Example
    Public Shared Sub Main()
        Dim temps As New SortedList(Of Temperature, String)

        ' Add entries to the sorted list, out of order.
        temps.Add(New Temperature(2017.15), "Boiling point of Lead")
        temps.Add(New Temperature(0), "Absolute zero")
        temps.Add(New Temperature(273.15), "Freezing point of water")
        temps.Add(New Temperature(5100.15), "Boiling point of Carbon")
        temps.Add(New Temperature(373.15), "Boiling point of water")
        temps.Add(New Temperature(600.65), "Melting point of Lead")

        For Each kvp As KeyValuePair(Of Temperature, String) In temps
            Console.WriteLine("{0} is {1} degrees Celsius.", kvp.Value, kvp.Key.Celsius)
        Next
    End Sub
End Class

' The example displays the following output:
'      Absolute zero is -273.15 degrees Celsius.
'      Freezing point of water is 0 degrees Celsius.
'      Boiling point of water is 100 degrees Celsius.
'      Melting point of Lead is 327.5 degrees Celsius.
'      Boiling point of Lead is 1744 degrees Celsius.
'      Boiling point of Carbon is 4827 degrees Celsius.
'

설명

이 인터페이스는 형식 값을 정렬 하거나 정렬할 수에 의해 구현 됩니다 하 고 제네릭 컬렉션 개체의 멤버를 정렬 하는 것에 대 한 강력한 형식의 비교 메서드를 제공 합니다.This interface is implemented by types whose values can be ordered or sorted and provides a strongly typed comparison method for ordering members of a generic collection object. 예를 들어, 1 개의 숫자 된 두 번째 수보다 클 수 있으며 한 문자열이 다른 것 보다 먼저 알파벳 순서로 나타날 수 있습니다.For example, one number can be larger than a second number, and one string can appear in alphabetical order before another. 구현 형식 단일 메서드를 정의 하는 것이 필요할 CompareTo(T), 하는 정렬 순서에서 현재 인스턴스의 위치 인지 나타내는 이전 후 동일한 형식의 두 번째 개체와 동일 합니다.It requires that implementing types define a single method, CompareTo(T), that indicates whether the position of the current instance in the sort order is before, after, or the same as a second object of the same type. 일반적으로 개발자 코드에서 직접 메서드를 호출 하지 됩니다.Typically, the method is not called directly from developer code. 대신 라고 자동으로 메서드에서 같은 List<T>.Sort()Add입니다.Instead, it is called automatically by methods such as List<T>.Sort() and Add.

일반적으로 형식을 제공 하는 IComparable<T> 구현도 구현 합니다.는 IEquatable<T> 인터페이스입니다.Typically, types that provide an IComparable<T> implementation also implement the IEquatable<T> interface. IEquatable<T> 인터페이스를 정의 합니다 Equals 메서드를 구현 하는 형식의 인스턴스가 같은지 여부를 확인 합니다.The IEquatable<T> interface defines the Equals method, which determines the equality of instances of the implementing type.

구현의 합니다 CompareTo(T) 메서드를 반환 해야 합니다는 Int32 있는 세 가지 값 중 하나는 다음 표에 나와 있는 것 처럼 합니다.The implementation of the CompareTo(T) method must return an Int32 that has one of three values, as shown in the following table.

Value 의미Meaning
0보다 작음Less than zero 이 개체에서 지정한 개체 앞에 CompareTo 정렬 순서에서 메서드.This object precedes the object specified by the CompareTo method in the sort order.
0Zero 이 현재 인스턴스에 지정 된 개체와 정렬 순서에서 같은 위치에서 발생 된 CompareTo 메서드 인수입니다.This current instance occurs in the same position in the sort order as the object specified by the CompareTo method argument.
0보다 큼Greater than zero 이 현재 인스턴스에 의해 지정 된 개체 다음에 오는 여 CompareTo 정렬 순서에서 메서드 인수입니다.This current instance follows the object specified by the CompareTo method argument in the sort order.

모든 숫자 형식 (같은 Int32 하 고 Double) 구현 IComparable<T>같이 StringChar, 및 DateTime합니다.All numeric types (such as Int32 and Double) implement IComparable<T>, as do String, Char, and DateTime. 사용자 지정 형식의 자체 구현을 제공 해야 IComparable<T> 정렬 되거나 정렬 될 개체 인스턴스를 사용 하도록 설정 합니다.Custom types should also provide their own implementation of IComparable<T> to enable object instances to be ordered or sorted.

구현자 참고

형식 매개 변수 대체는 IComparable<T> 이 인터페이스를 구현 하는 형식과 인터페이스입니다.Replace the type parameter of the IComparable<T> interface with the type that is implementing this interface.

구현 IComparable<T>하는 op_GreaterThan경우 op_GreaterThanOrEqual, 오버 로드 해야 합니다 op_LessThan, op_LessThanOrEqual, CompareTo(T), 및 연산자와 일치 하는 값을 반환할 합니다.If you implement IComparable<T>, you should overload the op_GreaterThan, op_GreaterThanOrEqual, op_LessThan, and op_LessThanOrEqual operators to return values that are consistent with CompareTo(T). 또한 구현 해야 IEquatable<T>합니다.In addition, you should also implement IEquatable<T>. 전체 정보 IEquatable<T> 는 문서를 참조 하세요.See the IEquatable<T> article for complete information.

메서드

CompareTo(T) CompareTo(T) CompareTo(T) CompareTo(T)

현재 인스턴스와 동일한 형식의 다른 개체를 비교하고 정렬 순서에서 현재 인스턴스의 위치가 다른 개체보다 앞인지, 뒤인지 또는 동일한지를 나타내는 정수를 반환합니다.Compares the current instance with another object of the same type and returns an integer that indicates whether the current instance precedes, follows, or occurs in the same position in the sort order as the other object.

적용 대상

추가 정보