IComparer<T>.Compare(T, T) 方法

定义

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。

public:
 int Compare(T x, T y);
public int Compare (T x, T y);
public int Compare (T? x, T? y);
abstract member Compare : 'T * 'T -> int
Public Function Compare (x As T, y As T) As Integer

参数

x
T

要比较的第一个对象。

y
T

要比较的第二个对象。

返回

Int32

一个有符号整数,指示 xy 的相对值,如下表所示。

含义
小于零x 小于 y
x 等于 y
大于零x 大于 y

示例

以下示例实现 接口, IComparer<T> 以根据对象的维度比较类型的 Box 对象。 此示例是为 类提供的更大示例的 Comparer<T> 一部分。

// 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

实现此方法,为类型 T提供自定义的排序顺序比较。

null允许与任何引用类型进行比较,并且不会生成异常。 空引用被视为小于任何不为 null 的引用。

适用于

另请参阅