此方法用于获取一个值，该值指示两个DateTime对象或一个DateTime实例与另一个对象或DateTime是否具有相同的值。此方法的重载列表中共有3种方法：
- 等于(DateTime，DateTime)
- 等于(DateTime)
- 等于(对象)
等于(DateTime，DateTime)
此方法用于返回一个值，该值指示两个DateTime实例是否具有相同的日期和时间值。
句法：
public static bool Equals (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：如果两个值相等，则此方法返回true；否则，返回true。否则为假。
下面的程序说明了DateTime.Equals(DateTime，DateTime)方法的用法：
范例1：
// C# program to demonstrate the
// DateTime.Equals(DateTime,
// DateTime) Method
using System;
using System.Globalization;
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 Equals() method;
bool value = DateTime.Equals(date1, date2);
// checking
if (value)
Console.Write("date1 is rquals to date2. ");
else
Console.Write("date1 is not equals to date2. ");
}
}
输出：
date1 is not equals to date2.范例2：
// C# program to demonstrate the
// DateTime.Equals(DateTime,
// DateTime) Method
using System;
using System.Globalization;
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 Equals() method;
bool value = DateTime.Equals(date1, date2);
// checking
if (value)
Console.WriteLine(" {0:d} is equals to"+
" {1:d}. ", date1, date2);
else
Console.WriteLine(" {0:d} is not equals"+
" to {1:d}. ", date1, date2);
}
}
输出：
1/3/2010 is not equals to 1/4/2010.
1/5/2010 is not equals to 1/4/2010.
1/5/2010 is equals to 1/5/2010.
等于(DateTime)
此方法用于返回一个值，该值指示此实例的值是否等于指定的DateTime实例的值。
句法：
public bool Equals (DateTime value);在这里，需要对象与该实例进行比较。
返回值：如果value参数等于此实例的值，则此方法返回true；否则，此方法返回true。否则为假。
下面的程序说明了DateTime.Equals(DateTime)方法的用法：
范例1：
// C# program to demonstrate the
// DateTime.Equals(DateTime) Method
using System;
using System.Globalization;
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 Equals() method;
bool value = date1.Equals(date2);
// checking
if (value)
Console.Write("date1 is rquals to date2. ");
else
Console.Write("date1 is not equals to date2. ");
}
}
输出：
date1 is not equals to date2. 范例2：
// C# program to demonstrate the
// DateTime.Equals(DateTime) Method
using System;
using System.Globalization;
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 Equals() method;
bool value = date1.Equals(date2);
// checking
if (value)
Console.WriteLine(" {0:d} is equals to"+
" {1:d}. ", date1, date2);
else
Console.WriteLine(" {0:d} is not equals "+
"to {1:d}. ", date1, date2);
}
}
输出：
01/03/2010 is not equals to 01/04/2010.
01/05/2010 is not equals to 01/04/2010.
01/05/2010 is equals to 01/05/2010.
等于(对象)
此方法用于返回一个值，该值指示此实例是否等于指定的对象。
句法：
public override bool Equals (object value);在这里，需要对象与该实例进行比较。
返回值：如果value参数等于此实例的值，则此方法返回true，否则返回false。
下面的程序说明了DateTime.Equals(Object)方法的用法：
范例1：
// C# program to demonstrate the
// DateTime.Equals(DateTime) Method
using System;
using System.Globalization;
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 Equals() method;
bool value = date1.Equals(date2);
// checking
if (value)
Console.Write("date1 is rquals to date2. ");
else
Console.Write("date1 is not equals to date2. ");
}
}
输出：
date1 is not equals to date2. 范例2：
// C# program to demonstrate the
// DateTime.Equals(DateTime) Method
using System;
using System.Globalization;
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 Equals() method;
bool value = date1.Equals(date2);
// checking
if (value)
Console.WriteLine(" {0:d} is equals "+
"to {1:d}. ", date1, date2);
else
Console.WriteLine(" {0:d} is not equals"+
" to {1:d}. ", date1, date2);
}
}
输出：
01/03/2010 is not equals to 01/04/2010.
01/05/2010 is not equals to 01/04/2010.
01/05/2010 is equals to 01/05/2010.
参考：
- https://docs.microsoft.com/zh-cn/dotnet/api/system.datetime.equals?view=netframework-4.7.2