此方法用于比较两个DateTime实例，并返回一个整数，该整数指示第一个实例是早于，等于还是晚于第二个实例。
句法：
public static int Compare (DateTime t1, DateTime t2);参数：
- t1：要比较的第一个对象。
- t2：要比较的第二个对象。
返回值：该方法返回一个带符号的数字，指示t1和t2的相对值。
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.
下面的程序说明了DateTime.Compare(DateTime，DateTime)方法的用法：
范例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. ");
}
}
输出：
date1 is later than date2.
范例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);
}
}
输出：
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.
参考：
- https://docs.microsoft.com/zh-cn/dotnet/api/system.datetime.compare?view=netframework-4.7.2