Date()
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Date()-
Returns a date either as a string or as a Date object.以字符串或Date对象的形式返回日期。Date()returns the current date as a string in在mongosh.mongosh中以字符串形式返回当前日期。new Date()returns the current date as a Date object.将当前日期作为mongoshwraps the Date object with theISODatehelper.Date对象返回。mongosh使用ISODate辅助对象包装Date对象。TheISODateis in UTC.ISODate以UTC为单位。
You can specify a particular date by passing an ISO-8601 date string with a year within the inclusive range您可以通过将年份在0through9999to thenew Date()constructor or theISODate()function.0到9999之间的ISO-8601日期字符串传递给new Date()构造函数或ISODate()函数来指定特定日期。These functions accept the following formats:这些函数接受以下格式:new Date("<YYYY-mm-dd>")returns the返回具有指定日期的ISODatewith the specified date.ISODate。new Date("<YYYY-mm-ddTHH:MM:ss>")specifies the datetime in the client's local timezone and returns the指定客户端本地时区中的日期时间,并返回指定日期时间(UTC)的ISODatewith the specified datetime in UTC.ISODate。new Date("<YYYY-mm-ddTHH:MM:ssZ>")specifies the datetime in UTC and returns the指定以UTC表示的日期时间,并返回以UTC表示指定日期时间的ISODatewith the specified datetime in UTC.ISODate。new Date(<integer>)specifies the datetime as milliseconds since the UNIX epoch (Jan 1, 1970), and returns the resulting将日期时间指定为自UNIX纪元(1970年1月1日)以来的毫秒,并返回生成的ISODateinstance.ISODate实例。
Behavior行为
Internally, Date objects are stored as a signed 64-bit integer representing the number of milliseconds since the Unix epoch (Jan 1, 1970).在内部,Date对象存储为一个带符号的64位整数,表示自Unix epoch(1970年1月1日)以来的毫秒数。
Not all database operations and drivers support the full 64-bit range. You may safely work with dates with years within the inclusive range 并非所有数据库操作和驱动程序都支持完整的64位范围。您可以安全地使用年份在0 through 9999.0到9999之间的日期。
Examples实例
Use Date in a Query在查询中使用日期
If no document with 如果_id equal to 1 exists in the products collection, the following operation inserts a document with the field dateAdded set to the current date:products集合中不存在_id等于1的文档,则以下操作将插入字段dateAdded设置为当前日期的文档:
db.products.updateOne(
{ _id: 1 },
{
$set: { item: "apple" },
$setOnInsert: { dateAdded: new Date() }
},
{ upsert: true }
)
See also: 另请参阅:
$currentDateNOW aggregation variable usageNOW聚合变量用法to update with aggregation pipeline要使用聚合管道进行更新
Return Date as a String字符串形式的返回日期
To return the date as a string, use the 要将日期作为字符串返回,请使用Date() method, as in the following example:Date()方法,如下例所示:
var myDateString = Date();
Return Date as Date Object返回日期作为Date对象
Date Objectmongosh wraps objects of Date type with the ISODate helper; however, the objects remain of type Date.mongosh使用ISODate辅助对象包装Date类型的对象;但是,对象仍然是Date类型。
The following example uses 以下示例使用new Date() to return Date object with the specified UTC datetime.new Date()返回具有指定UTC日期时间的Date对象。
var myDate = new Date("2016-05-18T16:00:00Z");
See also: 另请参阅:
Insert and Return ISODate Objects插入并返回ISODate对象
ISODate ObjectsYou can specify dates as 可以将日期指定为ISODate objects.ISODate对象。
The following example creates a 以下示例在cakeSales collection with ISODate objects in the orderDate field:orderDate字段中创建了一个带有ISODate对象的cakeSales集合:
db.cakeSales.insertMany( [
{ _id: 0, type: "chocolate", orderDate: new ISODate("2020-05-18T14:10:30Z") },
{ _id: 1, type: "strawberry", orderDate: new ISODate("2021-03-20T11:30:05Z") },
{ _id: 2, type: "vanilla", orderDate: new ISODate("2021-01-15T06:31:15Z") }
] )
The following example returns documents where the 以下示例返回orderDate is less than the ISODate specified in the $lt operator:orderDate小于$lt运算符中指定的ISODate的文档:
db.cakeSales.find( { orderDate: { $lt: ISODate("2021-02-25T10:03:46.000Z") } } )
Example output:示例输出:
[
{
_id: 0,
type: 'chocolate',
orderDate: ISODate("2020-05-18T14:10:30.000Z")
},
{
_id: 2,
type: 'vanilla',
orderDate: ISODate("2021-01-15T06:31:15.000Z")
}
]