c# - 比较时间时 DateTimeKind 是否被忽略？

Question

var dt1 = new DateTime(1, 1, 1, 0, 0, 0, 0, DateTimeKind.Unspecified);
var dt2 = new DateTime(1, 1, 1, 0, 0, 0, 0, DateTimeKind.Local);
var dt3 = new DateTime(1, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);

成对比较的结果让我大吃一惊:

Console.WriteLine(dt1 == dt2); // true
Console.WriteLine(dt1 == dt3); // true
Console.WriteLine(dt2 == dt3); // true

Answer 1

是的，Kind property比较 DateTime 值时会被忽略。

来自 referance source of == operator in DateTime structure :

public static bool operator ==(DateTime d1, DateTime d2)
{
    return d1.InternalTicks == d2.InternalTicks;
}

同样来自 DateTime.Compare documentation ¹:

To determine the relationship of t1 to t2, the Compare method compares the Ticks property of t1 and t2 but ignores their Kind property. Before comparing DateTime objects, ensure that the objects represent times in the same time zone.

1: ^{内部使用==运算符}