C# DateTime.Compare()用法及代碼示例

此方法用於比較兩個DateTime實例，並返回一個整數，該整數指示第一個實例是否早於，相同或晚於第二個實例。

用法:

public static int Compare (DateTime t1, DateTime t2);

參數：

t1:要比較的第一個對象。
t2:要比較的第二個對象。

返回值：此方法返回一個帶符號的數字，指示t1和t2的相對值。

Less than zero : If t1 is earlier than t2.
Zero : If t1 is the same as t2.
Greater than zero : If t1 is later than t2.

以下示例程序旨在說明DateTime.Compare(DateTime，DateTime)方法的用法：

示例1:

// C# program to demonstrate the 
// DateTime.Compare(DateTime, 
// DateTime) Method 
using System; 
  
class GFG { 
  
    // Main Method 
    public static void Main() 
    { 
        // creating object of DateTime 
        DateTime date1 = new DateTime(2010, 1,  
                                 1, 4, 0, 15); 
  
        // creating object of DateTime 
        DateTime date2 = new DateTime(2010, 1, 
                                 1, 4, 0, 14); 
  
        // comparing date1 and date2 
        // using Compare() method; 
        int value = DateTime.Compare(date1, date2); 
  
        // checking 
        if (value > 0) 
            Console.Write("date1 is later than date2. "); 
        else if (value < 0) 
            Console.Write("date1 is earlier than date2. "); 
        else
            Console.Write("date1 is the same as date2. "); 
    } 
}

輸出：

date1 is later than date2.

示例2:

// C# program to demonstrate the 
// DateTime.Compare(DateTime,  
// DateTime) Method 
using System; 
  
class GFG { 
  
    // Main Method 
    public static void Main() 
    { 
  
        // calling check() method 
        check(new DateTime(2010, 1, 3, 4, 0, 15), 
              new DateTime(2010, 1, 4, 4, 0, 15)); 
  
        check(new DateTime(2010, 1, 5, 4, 0, 15), 
              new DateTime(2010, 1, 4, 4, 0, 15)); 
  
        check(new DateTime(2010, 1, 5, 4, 0, 15), 
              new DateTime(2010, 1, 5, 4, 0, 15)); 
    } 
  
    public static void check(DateTime date1, 
                            DateTime date2) 
    { 
  
        // comparing date1 and date2 
        // using Compare() method; 
        int value = DateTime.Compare(date1, date2); 
  
        // checking 
        if (value > 0) 
            Console.WriteLine(" {0:d} is later than {1:d}. ", 
                                               date1, date2); 
        else if (value < 0) 
            Console.WriteLine(" {0:d} is earlier than {1:d}. ", 
                                                 date1, date2); 
        else
            Console.WriteLine(" {0:d} is the same as {1:d}. ", 
                                                date1, date2); 
    } 
}

輸出：

01/03/2010 is earlier than 01/04/2010. 
01/05/2010 is later than 01/04/2010. 
01/05/2010 is the same as 01/05/2010.

參考：

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

相關用法

注：本文由純淨天空篩選整理自RohitPrasad3大神的英文原創作品 DateTime.Compare() Method in C#。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。