System.Version.CompareTo 方法 (Version)

方法描述

将当前 Version 对象与指定的 Version 对象进行比较,并返回二者相对值的一个指示。

语法定义(C# System.Version.CompareTo 方法 (Version) 的用法)

public int CompareTo(
	Version value
)

参数/返回值

参数值/返回值 参数类型/返回类型 参数描述/返回描述
value System-Version 要与当前的 Version 对象进行比较的 Version 对象,或者为 null。
返回值 System.Int32 一个有符号整数,它指示两个对象的相对值,如下表所示。 含义 小于零 当前的 Version 对象是 value 之前的一个版本。 零 当前的 Version 对象是与 value 相同的版本。 大于零 当前 Version 对象是 value 之后的一个版本。 - 或 - value 为 null。

提示和注释

此方法实现 System.IComparable 接口,执行效果略好于 CompareTo 方法,因为它不必将 value 参数取消装箱。

Version 的所有部分按重要性递减顺序排列为:主要版本号、次要版本号、内部版本号和修订号。 假定未知部分比任何已知部分都旧。 例如:

1.1 版比 1.1.0 版旧

1.1 版比 1.1.1 版旧

1.1 版比 1.1.2.3 版旧

1.1.2 版比 1.1.2.4 版旧

1.2.5 版比 1.2.3.4 版新

System.Version.CompareTo 方法 (Version)例子

下面的代码示例演示几个值类型和引用类型的 CompareTo 方法的泛型和非泛型版本。

// 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
*/

异常

异常 异常描述

命名空间

namespace: System

程序集: mscorlib(在 mscorlib.dll 中)

版本信息

.NET Framework 受以下版本支持:4、3.5、3.0、2.0 .NET Framework Client Profile 受以下版本支持:4、3.5 SP1 受以下版本支持:

适用平台

Windows 7, Windows Vista SP1 或更高版本, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008(不支持服务器核心), Windows Server 2008 R2(支持 SP1 或更高版本的服务器核心), Windows Server 2003 SP2 .NET Framework 并不是对每个平台的所有版本都提供支持。有关支持的版本的列表,请参见.NET Framework 系统要求。