C# Double.CompareTo用法及代码示例

Double.CompareTo方法用于将当前实例与指定对象或Double对象进行比较。它将返回一个整数，该整数显示当前实例的值是大于，小于还是等于指定对象或Double对象的值。此方法的重载列表中有2种方法，如下所示：

CompareTo(Double)方法
CompareTo(Object)方法

Double.CompareTo(Double) Method

Double.CompareTo()方法用于将当前实例与指定的双精度浮点数进行比较，并返回一个整数，该整数显示此实例的值是小于，等于还是大于指定的double值。精度浮点数。

用法:

public int CompareTo (double value);

在这里，需要一个双精度浮点数进行比较。

返回值：此方法返回一个带符号的数字，指示该实例和值的相对值。

小于零：此实例小于value或该实例不是数字(NaN)并且value是数字。
零：此实例等于value，或者此实例和value都不是数字(NaN)，PositiveInfinity或NegativeInfinity。
大于零：此实例大于value或此实例是一个数字，而value不是一个数字(NaN)。

下面的程序说明Double.CompareTo(Double)方法的用法：

示例1:

// C# program to demonstrate the 
// Double.CompareTo(Double) 
// Method 
using System; 
using System.Globalization; 
  
class GFG { 
  
    // Main Method 
    public static void Main() 
    { 
        // Declaring and initializing value1 
        double value1 = 10d; 
  
        // Declaring and initializing value2 
        double value2 = 20d; 
  
        // compare both double value 
        // using CompareTo() method 
        int status = value1.CompareTo(value2); 
  
        // checking the status 
        if (status > 0) 
            Console.WriteLine("{0} is greater than {1}", 
                                       value1, value2); 
        else if (status < 0) 
            Console.WriteLine("{0} is less than {1}", 
                                     value1, value2); 
        else
            Console.WriteLine("{0} is equal to {1}", 
                                    value1, value2); 
    } 
}

输出：

10 is less than 20

示例2:

// C# program to demonstrate the 
// Double.CompareTo(Double) 
// Method 
using System; 
using System.Globalization; 
  
class GFG { 
  
    // Main Method 
    public static void Main() 
    { 
        // calling get() method 
        get(5d, 7d); 
        get(5.5d, 4.5d); 
        get(10d, 20d); 
        get(7.5d, 19.5d); 
    } 
  
    // defining get() method 
    public static void get(double value1, 
                           double value2) 
    { 
  
        // compare both double value 
        // using CompareTo() method 
        int status = value1.CompareTo(value2); 
  
        // checking the status 
        if (status > 0) 
            Console.WriteLine("{0} is greater than {1}", 
                                        value1, value2); 
        else if (status < 0) 
            Console.WriteLine("{0} is less than {1}", 
                                     value1, value2); 
        else
            Console.WriteLine("{0} is equal to {1}", 
                                    value1, value2); 
    } 
}

输出：

5 is less than 7
5.5 is greater than 4.5
10 is less than 20
7.5 is less than 19.5

Double.CompareTo(Object) Method

Double.CompareTo()方法用于将当前实例与指定对象进行比较，并返回一个整数，该整数指示当前实例的值是否小于，等于或大于指定对象的值。

用法:

public int CompareTo (object value);

在这里，它需要一个对象进行比较，或者为null。

返回值：此方法返回一个带符号的数字，指示该实例和值的相对值。

小于零：此实例小于value或该实例不是数字(NaN)并且value是数字。
零：此实例等于value，或者此实例和value都不是数字(NaN)，PositiveInfinity或NegativeInfinity。
大于零：此实例大于value或此实例是一个数字，而value不是一个数字(NaN)。

异常：如果value不是Double，则抛出ArgumentException。

下面的程序说明Double.CompareTo(Object)方法的用法：

示例1:

// C# program to demonstrate the 
// Double.CompareTo(object) 
// Method 
using System; 
using System.Globalization; 
  
class GFG { 
  
    // Main Method 
    public static void Main() 
    { 
        try { 
  
            // Declaring and initializing value1 
            double value1 = 10d; 
  
            // Declaring and initializing value2 
            object value2 = 20d; 
  
            // compare both double value 
            // using CompareTo() method 
            int status = value1.CompareTo(value2); 
  
            // checking the status 
            if (status > 0) 
                Console.WriteLine("{0} is greater than {1}", 
                                            value1, value2); 
            else if (status < 0) 
                Console.WriteLine("{0} is less than {1}", 
                                         value1, value2); 
            else
                Console.WriteLine("{0} is equal to {1}", 
                                        value1, value2); 
        } 
  
        catch (ArgumentException e)  
        { 
            Console.WriteLine("value2 must be double"); 
            Console.Write("Exception Thrown: "); 
            Console.Write("{0}", e.GetType(), e.Message); 
        } 
    } 
}

输出：

10 is less than 20

示例2:对于ArgumentException

// C# program to demonstrate the 
// Double.CompareTo(object) 
// Method 
using System; 
using System.Globalization; 
  
class GFG { 
  
    // Main Method 
    public static void Main() 
    { 
        try { 
  
            // Declaring and initializing value1 
            double value1 = 10d; 
  
            // Declaring and initializing value2 
            object value2 = 1 / 3; 
  
            // compare both double value 
            // using CompareTo() method 
            int status = value1.CompareTo(value2); 
  
            // checking the status 
            if (status > 0) 
                Console.WriteLine("{0} is greater than {1}", 
                                            value1, value2); 
  
            else if (status < 0) 
                Console.WriteLine("{0} is less than {1}", 
                                         value1, value2); 
            else
                Console.WriteLine("{0} is equal to {1}", 
                                        value1, value2); 
        } 
  
        catch (ArgumentException e)  
        { 
            Console.WriteLine("value2 must be double"); 
            Console.Write("Exception Thrown: "); 
            Console.Write("{0}", e.GetType(), e.Message); 
        } 
    } 
}

输出：

value2 must be double
Exception Thrown: System.ArgumentException

参考：

https://docs.microsoft.com/en-us/dotnet/api/system.double.compareto?view=netframework-4.7.2

相关用法

注：本文由纯净天空筛选整理自RohitPrasad3大神的英文原创作品 Double.CompareTo Method in C# with Examples。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。