Byte.CompareTo 方法

定义

命名空间:

System

程序集:

System.Runtime.dll

程序集:

netstandard.dll

程序集:

mscorlib.dll

将此实例与指定的对象或 Byte 进行比较，并返回二者相对值的指示。

重载

CompareTo(Byte)	将此实例与指定的 8 位无符号整数进行比较并返回对其相对值的指示。
CompareTo(Object)	将此实例与指定对象进行比较并返回一个对二者的相对值的指示。

CompareTo(Byte)

将此实例与指定的 8 位无符号整数进行比较并返回对其相对值的指示。

C#

public int CompareTo (byte value);

参数

value

Byte

要比较的 8 位无符号整数。

返回

Int32

一个有符号的整数，它指示此实例和 value 的相对顺序。

返回值	说明
小于零	此实例小于 value。
零	此实例等于 value。
大于零	此实例大于 value。

实现

CompareTo(T)

示例

下面的代码示例演示了多个值和引用类型的 方法的泛型和非 CompareTo 泛型版本。

C#

// This example demonstrates the generic and non-generic versions of the
// CompareTo method for several base types.
// The non-generic version takes a parameter of type Object, while the generic
// version takes a type-specific parameter, such as Boolean, Int32, or Double.

using System;

class Sample
{
    public static void Main()
    {
    string    nl = Environment.NewLine;
    string    msg = "{0}The following is the result of using the generic and non-generic{0}" +
                    "versions of the CompareTo method for several base types:{0}";

    DateTime  now = DateTime.Now;
// Time span = 11 days, 22 hours, 33 minutes, 44 seconds
    TimeSpan  tsX = new TimeSpan(11, 22, 33, 44);
// Version = 1.2.333.4
    Version   versX = new Version("1.2.333.4");
// Guid = CA761232-ED42-11CE-BACD-00AA0057B223
    Guid      guidX = new Guid("{CA761232-ED42-11CE-BACD-00AA0057B223}");

    Boolean  a1 = true,  a2 = true;
    Byte     b1 = 1,     b2 = 1;
    Int16    c1 = -2,    c2 = 2;
    Int32    d1 = 3,     d2 = 3;
    Int64    e1 = 4,     e2 = -4;
    Decimal  f1 = -5.5m, f2 = 5.5m;
    Single   g1 = 6.6f,  g2 = 6.6f;
    Double   h1 = 7.7d,  h2 = -7.7d;
    Char     i1 = 'A',   i2 = 'A';
    String   j1 = "abc", j2 = "abc";
    DateTime k1 = now,   k2 = now;
    TimeSpan l1 = tsX,   l2 = tsX;
    Version  m1 = versX, m2 = new Version("2.0");
    Guid     n1 = guidX, n2 = guidX;

// The following types are not CLS-compliant.
    SByte    w1 = 8,     w2 = 8;
    UInt16   x1 = 9,     x2 = 9;
    UInt32   y1 = 10,    y2 = 10;
    UInt64   z1 = 11,    z2 = 11;
//
    Console.WriteLine(msg, nl);
    try
        {
// The second and third Show method call parameters are automatically boxed because
// the second and third Show method declaration arguments expect type Object.

        Show("Boolean:  ", a1, a2, a1.CompareTo(a2), a1.CompareTo((Object)a2));
        Show("Byte:     ", b1, b2, b1.CompareTo(b2), b1.CompareTo((Object)b2));
        Show("Int16:    ", c1, c2, c1.CompareTo(c2), c1.CompareTo((Object)c2));
        Show("Int32:    ", d1, d2, d1.CompareTo(d2), d1.CompareTo((Object)d2));
        Show("Int64:    ", e1, e2, e1.CompareTo(e2), e1.CompareTo((Object)e2));
        Show("Decimal:  ", f1, f2, f1.CompareTo(f2), f1.CompareTo((Object)f2));
        Show("Single:   ", g1, g2, g1.CompareTo(g2), g1.CompareTo((Object)g2));
        Show("Double:   ", h1, h2, h1.CompareTo(h2), h1.CompareTo((Object)h2));
        Show("Char:     ", i1, i2, i1.CompareTo(i2), i1.CompareTo((Object)i2));
        Show("String:   ", j1, j2, j1.CompareTo(j2), j1.CompareTo((Object)j2));
        Show("DateTime: ", k1, k2, k1.CompareTo(k2), k1.CompareTo((Object)k2));
        Show("TimeSpan: ", l1, l2, l1.CompareTo(l2), l1.CompareTo((Object)l2));
        Show("Version:  ", m1, m2, m1.CompareTo(m2), m1.CompareTo((Object)m2));
        Show("Guid:     ", n1, n2, n1.CompareTo(n2), n1.CompareTo((Object)n2));
//
        Console.WriteLine("{0}The following types are not CLS-compliant:", nl);
        Show("SByte:    ", w1, w2, w1.CompareTo(w2), w1.CompareTo((Object)w2));
        Show("UInt16:   ", x1, x2, x1.CompareTo(x2), x1.CompareTo((Object)x2));
        Show("UInt32:   ", y1, y2, y1.CompareTo(y2), y1.CompareTo((Object)y2));
        Show("UInt64:   ", z1, z2, z1.CompareTo(z2), z1.CompareTo((Object)z2));
        }
    catch (Exception e)
        {
        Console.WriteLine(e);
        }
    }

    public static void Show(string caption, Object var1, Object var2,
                            int resultGeneric, int resultNonGeneric)
    {
    string relation;

    Console.Write(caption);
    if (resultGeneric == resultNonGeneric)
        {
        if      (resultGeneric < 0) relation = "less than";
        else if (resultGeneric > 0) relation = "greater than";
        else                        relation = "equal to";
        Console.WriteLine("{0} is {1} {2}", var1, relation, var2);
        }

// The following condition will never occur because the generic and non-generic
// CompareTo methods are equivalent.

    else
        {
        Console.WriteLine("Generic CompareTo = {0}; non-generic CompareTo = {1}",
                           resultGeneric, resultNonGeneric);
        }
   }
}
/*
This example produces the following results:

The following is the result of using the generic and non-generic versions of the
CompareTo method for several base types:

Boolean:  True is equal to True
Byte:     1 is equal to 1
Int16:    -2 is less than 2
Int32:    3 is equal to 3
Int64:    4 is greater than -4
Decimal:  -5.5 is less than 5.5
Single:   6.6 is equal to 6.6
Double:   7.7 is greater than -7.7
Char:     A is equal to A
String:   abc is equal to abc
DateTime: 12/1/2003 5:37:46 PM is equal to 12/1/2003 5:37:46 PM
TimeSpan: 11.22:33:44 is equal to 11.22:33:44
Version:  1.2.333.4 is less than 2.0
Guid:     ca761232-ed42-11ce-bacd-00aa0057b223 is equal to ca761232-ed42-11ce-bacd-00
aa0057b223

The following types are not CLS-compliant:
SByte:    8 is equal to 8
UInt16:   9 is equal to 9
UInt32:   10 is equal to 10
UInt64:   11 is equal to 11
*/

注解

此方法实现 接口，其性能比 方法略好，因为它不需要将 参数 System.IComparable<T> Byte.CompareTo(Object) 转换为 value 对象。

根据编程语言，可以编写一个方法，该方法的参数类型具有的位数 (比实例) CompareTo 更窄。 这是可能的，因为某些编程语言执行隐式扩大转换，该转换将参数表示为具有与 实例一样多位的类型。

例如，假设实例类型为 ， Int32 参数类型为 Byte 。 Microsoft C# 编译器生成指令来将 参数的值表示为 ，然后生成一个比较 实例的值和参数表示 Int32 Int32.CompareTo Int32 Int32 形式的方法。

请参阅编程语言的文档，以确定其编译器是否对数值类型执行隐式扩大转换。

另请参阅

• IComparable
• Equals(Object)

CompareTo(Object)

将此实例与指定对象进行比较并返回一个对二者的相对值的指示。

C#

public int CompareTo (object? value);

C#

public int CompareTo (object value);

参数

value

Object

要比较的对象，或为 null。

返回

Int32

一个有符号的整数，它指示此实例和 value 的相对顺序。

返回值	说明
小于零	此实例小于 value。
零	此实例等于 value。
大于零	此实例大于 value，或 value 为 null。

实现

CompareTo(Object)

例外

ArgumentException

value 不是 Byte。

示例

下面的代码示例演示 了 CompareTo 方法。

C#

public void Compare(Byte myByte)
{
   int myCompareResult;

   myCompareResult = MemberByte.CompareTo(myByte);

   if(myCompareResult > 0)
   {
      Console.WriteLine("{0} is less than the MemberByte value {1}", myByte.ToString(), MemberByte.ToString());
   }
   else if(myCompareResult < 0)
   {
      Console.WriteLine("{0} is greater than the MemberByte value {1}", myByte.ToString(), MemberByte.ToString());
   }
   else
   {
      Console.WriteLine("{0} is equal to the MemberByte value {1}", myByte.ToString(), MemberByte.ToString());
   }
}

注解

value 必须是 null 或 的实例 Byte ;否则将引发异常。

的任何 实例 Byte （无论其值如何）都被视为大于 null 。

实现此方法以支持 IComparable 接口。

另请参阅

• ArgumentException
• IComparable
• Equals(Object)