javascript setHours 日期设置为上一个日期

Question

我想使用 javascript 的 setHours() 方法将时间设置为 0，但它将月份中的日期更改为比实际日期少一。示例代码:

var d = new Date();  //2017-09-18T04:58:34.223Z
d.setHours(0,0,0,0);  //2017-09-17T18:30:00.000Z

Answer 1

The setHours() method sets the hours for a specified date according to local time, and returns the number of milliseconds since 1 January 1970 00:00:00 UTC until the time represented by the updated Date instance.

要将时间设置为世界时午夜，请使用 setUTCHours() .

The getUTCHours() method returns the hours in the specified date according to universal time.

var date = new Date();
console.log(date.toISOString());
date.setUTCHours(0,0,0,0);
console.log(date.toISOString());