IComparer<T> IComparer<T> IComparer<T> IComparer<T> Interface

定义

定义类型为比较两个对象而实现的方法。Defines a method that a type implements to compare two objects.

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

类型参数

T

要比较的对象的类型。The type of objects to compare.

派生

示例

下面的示例实现IComparer<T>接口来比较类型的对象Box根据其维度。The following example implements the IComparer<T> interface to compare objects of type Box according to their dimensions. 此示例摘自一个更大的示例为提供Comparer<T>类。This example is part of a larger example provided for the Comparer<T> class.

// This class is not demonstrated in the Main method
// and is provided only to show how to implement
// the interface. It is recommended to derive
// from Comparer<T> instead of implementing IComparer<T>.
public class BoxComp : IComparer<Box>
{
    // Compares by Height, Length, and Width.
    public int Compare(Box x, Box y)
    {
        if (x.Height.CompareTo(y.Height) != 0)
        {
            return x.Height.CompareTo(y.Height);
        }
        else if (x.Length.CompareTo(y.Length) != 0)
        {
            return x.Length.CompareTo(y.Length);
        }
        else if (x.Width.CompareTo(y.Width) != 0)
        {
            return x.Width.CompareTo(y.Width);
        }
        else
        {
            return 0;
        }
    }
}
' This class is not demonstrated in the Main method
' and is provided only to show how to implement
' the interface. It is recommended to derive
' from Comparer<T> instead of implementing IComparer<T>.
Public Class BoxComp
	Implements IComparer(Of Box)
	' Compares by Height, Length, and Width.
    Public Function Compare(ByVal x As Box, ByVal y As Box) As Integer Implements _
                                                IComparer(Of Box).Compare
        If x.Height.CompareTo(y.Height) <> 0 Then
            Return x.Height.CompareTo(y.Height)
        ElseIf x.Length.CompareTo(y.Length) <> 0 Then
            Return x.Length.CompareTo(y.Length)
        ElseIf x.Width.CompareTo(y.Width) <> 0 Then
            Return x.Width.CompareTo(y.Width)
        Else
            Return 0
        End If
    End Function
End Class

注解

此接口用于List<T>.SortList<T>.BinarySearch方法。This interface is used with the List<T>.Sort and List<T>.BinarySearch methods. 它提供了一种方法自定义集合的排序顺序。It provides a way to customize the sort order of a collection. 实现此接口的类包括SortedDictionary<TKey,TValue>SortedList<TKey,TValue>泛型类。Classes that implement this interface include the SortedDictionary<TKey,TValue> and SortedList<TKey,TValue> generic classes.

此接口的默认实现是Comparer<T>类。The default implementation of this interface is the Comparer<T> class. StringComparer类实现此接口类型StringThe StringComparer class implements this interface for type String.

此接口支持排序的比较。This interface supports ordering comparisons. 也就是说,当Compare方法返回 0,这意味着两个对象进行排序相同。That is, when the Compare method returns 0, it means that two objects sort the same. 通过提供完全相等比较实现IEqualityComparer<T>泛型接口。Implementation of exact equality comparisons is provided by the IEqualityComparer<T> generic interface.

我们建议从派生Comparer<T>类而不是实现IComparer<T>接口,因为Comparer<T>类提供的显式接口实现IComparer.Compare方法和Default属性,获取对象的默认比较器。We recommend that you derive from the Comparer<T> class instead of implementing the IComparer<T> interface, because the Comparer<T> class provides an explicit interface implementation of the IComparer.Compare method and the Default property that gets the default comparer for the object.

方法

Compare(T, T) Compare(T, T) Compare(T, T) Compare(T, T)

比较两个对象并返回一个值,该值指示一个对象小于、等于还是大于另一个对象。Compares two objects and returns a value indicating whether one is less than, equal to, or greater than the other.

适用于

另请参阅