IComparable<T>.CompareTo(T) IComparable<T>.CompareTo(T) IComparable<T>.CompareTo(T) IComparable<T>.CompareTo(T) Method

정의

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.

public:
 int CompareTo(T other);
public int CompareTo (T other);
abstract member CompareTo : 'T -> int
Public Function CompareTo (other As T) As Integer

매개 변수

other

이 인스턴스와 비교할 개체입니다.An object to compare with this instance.

반환

비교되는 개체의 상대 순서를 나타내는 값입니다.A value that indicates the relative order of the objects being compared. 반환 값에는 다음과 같은 의미가 있습니다.The return value has these meanings:

Value 의미Meaning
0보다 작음Less than zero 이 인스턴스가 정렬 순서에서 other 앞에 옵니다.This instance precedes other in the sort order.

0Zero 이 인스턴스가 정렬 순서에서 other와 동일한 위치에 있습니다.This instance occurs in the same position in the sort order as other.

0보다 큼Greater than zero 이 인스턴스가 정렬 순서에서 other 뒤에 옵니다.This instance follows other in the sort order.

예제

다음 코드 예제 구현의 IComparable<T> 간단 Temperature 개체입니다.The following code 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

CompareTo 제네릭 컬렉션 개체의 멤버를 정렬 하는 강력한 형식의 비교 메서드를 제공 합니다.CompareTo provides a strongly typed comparison method for ordering members of a generic collection object. 이 인해이 호출 되지 개발자 코드에서 직접.Because of this, it is usually 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.

이 메서드는 정의 이며 효과가 사용 되는 특정 클래스 또는 값 형식으로 구현 해야 합니다.This method is only a definition and must be implemented by a specific class or value type to have effect. 섹션 ("앞 에", "와 동일한 위치에서 발생" 및 "따릅니다)은 특정 구현에 따라 반환 값에 지정 된 비교 의미 합니다.The meaning of the comparisons specified in the Return Values section ("precedes", "occurs in the same position as", and "follows) depends on the particular implementation.

모든 개체 정의 따라 보다 큰 비교 null, 두 null 참조가 서로 같은지 비교 합니다.By definition, any object compares greater than null, and two null references compare equal to each other.

구현자 참고

개체 A, B 및 C의 경우 다음 참 이어야 합니다.For objects A, B, and C, the following must be true: A.CompareTo(A) 0을 반환 해야 합니다.A.CompareTo(A) is required to return zero.

하는 경우 A.CompareTo(B) 그런 다음 반환 0 B.CompareTo(A) 0을 반환 하는 데 필요한 합니다.If A.CompareTo(B) returns zero, then B.CompareTo(A) is required to return zero.

하는 경우 A.CompareTo(B) 0을 반환 하 고 B.CompareTo(C) 반환 0, A.CompareTo(C) 0을 반환 하는 데 필요한 합니다.If A.CompareTo(B) returns zero and B.CompareTo(C) returns zero, then A.CompareTo(C) is required to return zero.

하는 경우 A.CompareTo(B) 그런 다음 0이 아닌 값을 반환 B.CompareTo(A) 부호가 다른 값을 반환 하는 데 필요한 합니다.If A.CompareTo(B) returns a value other than zero, then B.CompareTo(A) is required to return a value of the opposite sign.

경우 A.CompareTo(B) 값을 반환 x 는 0과 같지 않은 및 B.CompareTo(C) 값을 반환 y 같은 부호의 x, 한 다음 A.CompareTo(C) 같은 부호 값을 반환 하는 데 필요한 xy합니다.If A.CompareTo(B) returns a value x that is not equal to zero, and B.CompareTo(C) returns a value y of the same sign as x, then A.CompareTo(C) is required to return a value of the same sign as x and y.

호출자 참고

사용 된 CompareTo(T) 클래스 인스턴스의 순서를 결정 하는 방법입니다.Use the CompareTo(T) method to determine the ordering of instances of a class.

적용 대상

추가 정보