Struct chrono::DateTime

pub struct DateTime<Tz: TimeZone> { /* private fields */ }

ISO 8601 combined date and time with time zone.

There are some constructors implemented here (the from_* methods), but the general-purpose constructors are all via the methods on the TimeZone implementations.

Implementations

impl<Tz: TimeZone> DateTime<Tz>

pub fn from_utc(datetime: NaiveDateTime, offset: Tz::Offset) -> DateTime<Tz>

Makes a new DateTime with given UTC datetime and offset. The local datetime should be constructed via the TimeZone trait.

Example

use chrono::{DateTime, TimeZone, NaiveDateTime, Utc};

let dt = DateTime::<Utc>::from_utc(NaiveDateTime::from_timestamp(61, 0), Utc);
assert_eq!(Utc.timestamp(61, 0), dt);

pub fn from_local(datetime: NaiveDateTime, offset: Tz::Offset) -> DateTime<Tz>

Makes a new DateTime with given local datetime and offset that presents local timezone.

Example

use chrono::DateTime;
use chrono::naive::NaiveDate;
use chrono::offset::{Utc, FixedOffset};

let naivedatetime_utc = NaiveDate::from_ymd(2000, 1, 12).and_hms(2, 0, 0);
let datetime_utc = DateTime::<Utc>::from_utc(naivedatetime_utc, Utc);

let timezone_east = FixedOffset::east(8 * 60 * 60);
let naivedatetime_east = NaiveDate::from_ymd(2000, 1, 12).and_hms(10, 0, 0);
let datetime_east = DateTime::<FixedOffset>::from_local(naivedatetime_east, timezone_east);

let timezone_west = FixedOffset::west(7 * 60 * 60);
let naivedatetime_west = NaiveDate::from_ymd(2000, 1, 11).and_hms(19, 0, 0);
let datetime_west = DateTime::<FixedOffset>::from_local(naivedatetime_west, timezone_west);
assert_eq!(datetime_east, datetime_utc.with_timezone(&timezone_east));
assert_eq!(datetime_west, datetime_utc.with_timezone(&timezone_west));

pub fn date(&self) -> Date<Tz>

Retrieves a date component

Unless you are immediately planning on turning this into a DateTime with the same Timezone you should use the date_naive method.

use chrono::prelude::*;

let date: Date<Utc> = Utc.ymd(2020, 1, 1);
let dt: DateTime<Utc> = date.and_hms(0, 0, 0);

assert_eq!(dt.date(), date);

assert_eq!(dt.date().and_hms(1, 1, 1), date.and_hms(1, 1, 1));

pub fn date_naive(&self) -> NaiveDate

Retrieves the Date without an associated timezone

NaiveDate is a more well-defined type, and has more traits implemented on it, so should be preferred to Date any time you truly want to operate on Dates.

use chrono::prelude::*;

let date: DateTime<Utc> = Utc.ymd(2020, 1, 1).and_hms(0, 0, 0);
let other: DateTime<FixedOffset> = FixedOffset::east(23).ymd(2020, 1, 1).and_hms(0, 0, 0);
assert_eq!(date.date_naive(), other.date_naive());

pub fn time(&self) -> NaiveTime

Retrieves a time component. Unlike date, this is not associated to the time zone.

pub fn timestamp(&self) -> i64

Returns the number of non-leap seconds since January 1, 1970 0:00:00 UTC (aka “UNIX timestamp”).

pub fn timestamp_millis(&self) -> i64

Returns the number of non-leap-milliseconds since January 1, 1970 UTC

Note that this does reduce the number of years that can be represented from ~584 Billion to ~584 Million. (If this is a problem, please file an issue to let me know what domain needs millisecond precision over billions of years, I’m curious.)

Example

use chrono::Utc;
use chrono::TimeZone;

let dt = Utc.ymd(1970, 1, 1).and_hms_milli(0, 0, 1, 444);
assert_eq!(dt.timestamp_millis(), 1_444);

let dt = Utc.ymd(2001, 9, 9).and_hms_milli(1, 46, 40, 555);
assert_eq!(dt.timestamp_millis(), 1_000_000_000_555);

pub fn timestamp_micros(&self) -> i64

Returns the number of non-leap-microseconds since January 1, 1970 UTC

Note that this does reduce the number of years that can be represented from ~584 Billion to ~584 Thousand. (If this is a problem, please file an issue to let me know what domain needs microsecond precision over millennia, I’m curious.)

Example

use chrono::Utc;
use chrono::TimeZone;

let dt = Utc.ymd(1970, 1, 1).and_hms_micro(0, 0, 1, 444);
assert_eq!(dt.timestamp_micros(), 1_000_444);

let dt = Utc.ymd(2001, 9, 9).and_hms_micro(1, 46, 40, 555);
assert_eq!(dt.timestamp_micros(), 1_000_000_000_000_555);

pub fn timestamp_nanos(&self) -> i64

Returns the number of non-leap-nanoseconds since January 1, 1970 UTC

Note that this does reduce the number of years that can be represented from ~584 Billion to ~584. (If this is a problem, please file an issue to let me know what domain needs nanosecond precision over millennia, I’m curious.)

Example

use chrono::Utc;
use chrono::TimeZone;

let dt = Utc.ymd(1970, 1, 1).and_hms_nano(0, 0, 1, 444);
assert_eq!(dt.timestamp_nanos(), 1_000_000_444);

let dt = Utc.ymd(2001, 9, 9).and_hms_nano(1, 46, 40, 555);
assert_eq!(dt.timestamp_nanos(), 1_000_000_000_000_000_555);

pub fn timestamp_subsec_millis(&self) -> u32

Returns the number of milliseconds since the last second boundary

warning: in event of a leap second, this may exceed 999

note: this is not the number of milliseconds since January 1, 1970 0:00:00 UTC

pub fn timestamp_subsec_micros(&self) -> u32

Returns the number of microseconds since the last second boundary

warning: in event of a leap second, this may exceed 999_999

note: this is not the number of microseconds since January 1, 1970 0:00:00 UTC

pub fn timestamp_subsec_nanos(&self) -> u32

Returns the number of nanoseconds since the last second boundary

warning: in event of a leap second, this may exceed 999_999_999

note: this is not the number of nanoseconds since January 1, 1970 0:00:00 UTC

pub fn offset(&self) -> &Tz::Offset

Retrieves an associated offset from UTC.

pub fn timezone(&self) -> Tz

Retrieves an associated time zone.

pub fn with_timezone<Tz2: TimeZone>(&self, tz: &Tz2) -> DateTime<Tz2>

Changes the associated time zone. The returned DateTime references the same instant of time from the perspective of the provided time zone.

pub fn checked_add_signed(self, rhs: OldDuration) -> Option<DateTime<Tz>>

Adds given Duration to the current date and time.

Returns None when it will result in overflow.

pub fn checked_sub_signed(self, rhs: OldDuration) -> Option<DateTime<Tz>>

Subtracts given Duration from the current date and time.

Returns None when it will result in overflow.

pub fn signed_duration_since<Tz2: TimeZone>(
    self,
    rhs: DateTime<Tz2>
) -> OldDuration

Subtracts another DateTime from the current date and time. This does not overflow or underflow at all.

pub fn naive_utc(&self) -> NaiveDateTime

Returns a view to the naive UTC datetime.

pub fn naive_local(&self) -> NaiveDateTime

Returns a view to the naive local datetime.

pub fn years_since(&self, base: Self) -> Option<u32>

Retrieve the elapsed years from now to the given DateTime.

pub const MIN_UTC: DateTime<Utc> = _

The minimum possible DateTime<Utc>.

pub const MAX_UTC: DateTime<Utc> = _

The maximum possible DateTime<Utc>.

impl DateTime<FixedOffset>

pub fn parse_from_rfc2822(s: &str) -> ParseResult<DateTime<FixedOffset>>

Parses an RFC 2822 date and time string such as Tue, 1 Jul 2003 10:52:37 +0200, then returns a new DateTime with a parsed FixedOffset.

RFC 2822 is the internet message standard that specifies the representation of times in HTTP and email headers.

assert_eq!(
    DateTime::parse_from_rfc2822("Wed, 18 Feb 2015 23:16:09 GMT").unwrap(),
    FixedOffset::east(0).ymd(2015, 2, 18).and_hms(23, 16, 9)
);

pub fn parse_from_rfc3339(s: &str) -> ParseResult<DateTime<FixedOffset>>

Parses an RFC 3339 and ISO 8601 date and time string such as 1996-12-19T16:39:57-08:00, then returns a new DateTime with a parsed FixedOffset.

Why isn’t this named parse_from_iso8601? That’s because ISO 8601 allows some freedom over the syntax and RFC 3339 exercises that freedom to rigidly define a fixed format.

pub fn parse_from_str(s: &str, fmt: &str) -> ParseResult<DateTime<FixedOffset>>

Parses a string with the specified format string and returns a new DateTime with a parsed FixedOffset.

See the crate::format::strftime module on the supported escape sequences.

See also TimeZone::datetime_from_str which gives a local DateTime on specific time zone.

Note that this method requires a timezone in the string. See NaiveDateTime::parse_from_str for a version that does not require a timezone in the to-be-parsed str.

Example

use chrono::{DateTime, FixedOffset, TimeZone};

let dt = DateTime::parse_from_str(
    "1983 Apr 13 12:09:14.274 +0000", "%Y %b %d %H:%M:%S%.3f %z");
assert_eq!(dt, Ok(FixedOffset::east(0).ymd(1983, 4, 13).and_hms_milli(12, 9, 14, 274)));

impl<Tz: TimeZone> DateTime<Tz>where
    Tz::Offset: Display,

pub fn to_rfc2822(&self) -> String

Returns an RFC 2822 date and time string such as Tue, 1 Jul 2003 10:52:37 +0200.

pub fn to_rfc3339(&self) -> String

Returns an RFC 3339 and ISO 8601 date and time string such as 1996-12-19T16:39:57-08:00.

pub fn to_rfc3339_opts(&self, secform: SecondsFormat, use_z: bool) -> String

Return an RFC 3339 and ISO 8601 date and time string with subseconds formatted as per a SecondsFormat.

If passed use_z true and the timezone is UTC (offset 0), use ‘Z’, as per Fixed::TimezoneOffsetColonZ If passed use_z false, use Fixed::TimezoneOffsetColon

Examples

let dt = Utc.ymd(2018, 1, 26).and_hms_micro(18, 30, 9, 453_829);
assert_eq!(dt.to_rfc3339_opts(SecondsFormat::Millis, false),
           "2018-01-26T18:30:09.453+00:00");
assert_eq!(dt.to_rfc3339_opts(SecondsFormat::Millis, true),
           "2018-01-26T18:30:09.453Z");
assert_eq!(dt.to_rfc3339_opts(SecondsFormat::Secs, true),
           "2018-01-26T18:30:09Z");

let pst = FixedOffset::east(8 * 60 * 60);
let dt = pst.ymd(2018, 1, 26).and_hms_micro(10, 30, 9, 453_829);
assert_eq!(dt.to_rfc3339_opts(SecondsFormat::Secs, true),
           "2018-01-26T10:30:09+08:00");

pub fn format_with_items<'a, I, B>(&self, items: I) -> DelayedFormat<I>where
    I: Iterator<Item = B> + Clone,
    B: Borrow<Item<'a>>,

Formats the combined date and time with the specified formatting items.

pub fn format<'a>(&self, fmt: &'a str) -> DelayedFormat<StrftimeItems<'a>>

Formats the combined date and time with the specified format string. See the crate::format::strftime module on the supported escape sequences.

Example

use chrono::prelude::*;

let date_time: DateTime<Utc> = Utc.ymd(2017, 04, 02).and_hms(12, 50, 32);
let formatted = format!("{}", date_time.format("%d/%m/%Y %H:%M"));
assert_eq!(formatted, "02/04/2017 12:50");

Trait Implementations

impl<Tz: TimeZone> Add<Duration> for DateTime<Tz>

type Output = DateTime<Tz>

The resulting type after applying the + operator.

fn add(self, rhs: OldDuration) -> DateTime<Tz>

Performs the + operation.

impl<Tz: TimeZone> Add<FixedOffset> for DateTime<Tz>

type Output = DateTime<Tz>

The resulting type after applying the + operator.

fn add(self, rhs: FixedOffset) -> DateTime<Tz>

Performs the + operation.

impl<Tz: TimeZone> AddAssign<Duration> for DateTime<Tz>

fn add_assign(&mut self, rhs: OldDuration)

Performs the += operation.

impl<Tz: Clone + TimeZone> Clone for DateTime<Tz>where
    Tz::Offset: Clone,

fn clone(&self) -> DateTime<Tz>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<Tz: TimeZone> Datelike for DateTime<Tz>

fn year(&self) -> i32

Returns the year number in the calendar date.

fn month(&self) -> u32

Returns the month number starting from 1.

fn month0(&self) -> u32

Returns the month number starting from 0.

fn day(&self) -> u32

Returns the day of month starting from 1.

fn day0(&self) -> u32

Returns the day of month starting from 0.

fn ordinal(&self) -> u32

Returns the day of year starting from 1.

fn ordinal0(&self) -> u32

Returns the day of year starting from 0.

fn weekday(&self) -> Weekday

Returns the day of week.

fn iso_week(&self) -> IsoWeek

Returns the ISO week.

fn with_year(&self, year: i32) -> Option<DateTime<Tz>>

Makes a new value with the year number changed.

fn with_month(&self, month: u32) -> Option<DateTime<Tz>>

Makes a new value with the month number (starting from 1) changed.

fn with_month0(&self, month0: u32) -> Option<DateTime<Tz>>

Makes a new value with the month number (starting from 0) changed.

fn with_day(&self, day: u32) -> Option<DateTime<Tz>>

Makes a new value with the day of month (starting from 1) changed.

fn with_day0(&self, day0: u32) -> Option<DateTime<Tz>>

Makes a new value with the day of month (starting from 0) changed.

fn with_ordinal(&self, ordinal: u32) -> Option<DateTime<Tz>>

Makes a new value with the day of year (starting from 1) changed.

fn with_ordinal0(&self, ordinal0: u32) -> Option<DateTime<Tz>>

Makes a new value with the day of year (starting from 0) changed.

fn year_ce(&self) -> (bool, u32)

Returns the absolute year number starting from 1 with a boolean flag, which is false when the year predates the epoch (BCE/BC) and true otherwise (CE/AD).

fn num_days_from_ce(&self) -> i32

Counts the days in the proleptic Gregorian calendar, with January 1, Year 1 (CE) as day 1.

impl<Tz: TimeZone> Debug for DateTime<Tz>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for DateTime<FixedOffset>

fn default() -> Self

Returns the “default value” for a type.

impl Default for DateTime<Local>

fn default() -> Self

Returns the “default value” for a type.

impl Default for DateTime<Utc>

fn default() -> Self

Returns the “default value” for a type.

impl<Tz: TimeZone> Display for DateTime<Tz>where
    Tz::Offset: Display,

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<Tz: TimeZone> DurationRound for DateTime<Tz>

type Err = RoundingError

Error that can occur in rounding or truncating

fn duration_round(self, duration: Duration) -> Result<Self, Self::Err>

Return a copy rounded by Duration.

fn duration_trunc(self, duration: Duration) -> Result<Self, Self::Err>

Return a copy truncated by Duration.

impl From<DateTime<FixedOffset>> for DateTime<Local>

Convert a DateTime<FixedOffset> instance into a DateTime<Local> instance.

fn from(src: DateTime<FixedOffset>) -> Self

Convert this DateTime<FixedOffset> instance into a DateTime<Local> instance.

Conversion is performed via DateTime::with_timezone. Returns the equivalent value in local time.

impl From<DateTime<FixedOffset>> for DateTime<Utc>

Convert a DateTime<FixedOffset> instance into a DateTime<Utc> instance.

fn from(src: DateTime<FixedOffset>) -> Self

Convert this DateTime<FixedOffset> instance into a DateTime<Utc> instance.

Conversion is performed via DateTime::with_timezone, accounting for the timezone difference.

impl From<DateTime<Local>> for DateTime<FixedOffset>

Convert a DateTime<Local> instance into a DateTime<FixedOffset> instance.

fn from(src: DateTime<Local>) -> Self

Convert this DateTime<Local> instance into a DateTime<FixedOffset> instance.

Conversion is performed via DateTime::with_timezone. Note that the converted value returned by this will be created with a fixed timezone offset of 0.

impl From<DateTime<Local>> for DateTime<Utc>

Convert a DateTime<Local> instance into a DateTime<Utc> instance.

fn from(src: DateTime<Local>) -> Self

Convert this DateTime<Local> instance into a DateTime<Utc> instance.

Conversion is performed via DateTime::with_timezone, accounting for the difference in timezones.

impl<Tz: TimeZone> From<DateTime<Tz>> for SystemTime

fn from(dt: DateTime<Tz>) -> SystemTime

Converts to this type from the input type.

impl From<DateTime<Utc>> for DateTime<FixedOffset>

Convert a DateTime<Utc> instance into a DateTime<FixedOffset> instance.

fn from(src: DateTime<Utc>) -> Self

Convert this DateTime<Utc> instance into a DateTime<FixedOffset> instance.

Conversion is done via DateTime::with_timezone. Note that the converted value returned by this will be created with a fixed timezone offset of 0.

impl From<DateTime<Utc>> for DateTime<Local>

Convert a DateTime<Utc> instance into a DateTime<Local> instance.

fn from(src: DateTime<Utc>) -> Self

Convert this DateTime<Utc> instance into a DateTime<Local> instance.

Conversion is performed via DateTime::with_timezone, accounting for the difference in timezones.

impl From<SystemTime> for DateTime<Local>

fn from(t: SystemTime) -> DateTime<Local>

Converts to this type from the input type.

impl From<SystemTime> for DateTime<Utc>

fn from(t: SystemTime) -> DateTime<Utc>

Converts to this type from the input type.

impl FromStr for DateTime<FixedOffset>

Accepts a relaxed form of RFC3339. A space or a ‘T’ are acepted as the separator between the date and time parts. Additional spaces are allowed between each component.

All of these examples are equivalent:

"2012-12-12T12:12:12Z".parse::<DateTime<FixedOffset>>();
"2012-12-12 12:12:12Z".parse::<DateTime<FixedOffset>>();
"2012-  12-12T12:  12:12Z".parse::<DateTime<FixedOffset>>();

type Err = ParseError

The associated error which can be returned from parsing.

fn from_str(s: &str) -> ParseResult<DateTime<FixedOffset>>

Parses a string s to return a value of this type.

impl FromStr for DateTime<Local>

Accepts a relaxed form of RFC3339. A space or a ‘T’ are acepted as the separator between the date and time parts. Additional spaces are allowed between each component.

All of these examples are equivalent:

"2012-12-12T12:12:12Z".parse::<DateTime<Local>>();
"2012-12-12 12:12:12Z".parse::<DateTime<Local>>();
"2012-  12-12T12:  12:12Z".parse::<DateTime<Local>>();

type Err = ParseError

The associated error which can be returned from parsing.

fn from_str(s: &str) -> ParseResult<DateTime<Local>>

Parses a string s to return a value of this type.

impl FromStr for DateTime<Utc>

Accepts a relaxed form of RFC3339. A space or a ‘T’ are acepted as the separator between the date and time parts. Additional spaces are allowed between each component.

All of these examples are equivalent:

"2012-12-12T12:12:12Z".parse::<DateTime<Utc>>();
"2012-12-12 12:12:12Z".parse::<DateTime<Utc>>();
"2012-  12-12T12:  12:12Z".parse::<DateTime<Utc>>();

type Err = ParseError

The associated error which can be returned from parsing.

fn from_str(s: &str) -> ParseResult<DateTime<Utc>>

Parses a string s to return a value of this type.

impl<Tz: TimeZone> Hash for DateTime<Tz>

fn hash<H: Hasher>(&self, state: &mut H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)where
    H: Hasher,
    Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<Tz: TimeZone> Ord for DateTime<Tz>

fn cmp(&self, other: &DateTime<Tz>) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Selfwhere
    Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Selfwhere
    Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Selfwhere
    Self: Sized + PartialOrd<Self>,

Restrict a value to a certain interval.

impl<Tz: TimeZone, Tz2: TimeZone> PartialEq<DateTime<Tz2>> for DateTime<Tz>

fn eq(&self, other: &DateTime<Tz2>) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<Tz: TimeZone, Tz2: TimeZone> PartialOrd<DateTime<Tz2>> for DateTime<Tz>

fn partial_cmp(&self, other: &DateTime<Tz2>) -> Option<Ordering>

Compare two DateTimes based on their true time, ignoring time zones

Example

use chrono::prelude::*;

let earlier = Utc.ymd(2015, 5, 15).and_hms(2, 0, 0).with_timezone(&FixedOffset::west(1 * 3600));
let later   = Utc.ymd(2015, 5, 15).and_hms(3, 0, 0).with_timezone(&FixedOffset::west(5 * 3600));

assert_eq!(earlier.to_string(), "2015-05-15 01:00:00 -01:00");
assert_eq!(later.to_string(), "2015-05-14 22:00:00 -05:00");

assert!(later > earlier);

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl<Tz: TimeZone> Sub<DateTime<Tz>> for DateTime<Tz>

type Output = Duration

The resulting type after applying the - operator.

fn sub(self, rhs: DateTime<Tz>) -> OldDuration

Performs the - operation.

impl<Tz: TimeZone> Sub<Duration> for DateTime<Tz>

type Output = DateTime<Tz>

The resulting type after applying the - operator.

fn sub(self, rhs: OldDuration) -> DateTime<Tz>

Performs the - operation.

impl<Tz: TimeZone> Sub<FixedOffset> for DateTime<Tz>

type Output = DateTime<Tz>

The resulting type after applying the - operator.

fn sub(self, rhs: FixedOffset) -> DateTime<Tz>

Performs the - operation.

impl<Tz: TimeZone> SubAssign<Duration> for DateTime<Tz>

fn sub_assign(&mut self, rhs: OldDuration)

Performs the -= operation.

impl<Tz: TimeZone> Timelike for DateTime<Tz>

fn hour(&self) -> u32

Returns the hour number from 0 to 23.

fn minute(&self) -> u32

Returns the minute number from 0 to 59.

fn second(&self) -> u32

Returns the second number from 0 to 59.

fn nanosecond(&self) -> u32

Returns the number of nanoseconds since the whole non-leap second. The range from 1,000,000,000 to 1,999,999,999 represents the leap second.

fn with_hour(&self, hour: u32) -> Option<DateTime<Tz>>

Makes a new value with the hour number changed.

fn with_minute(&self, min: u32) -> Option<DateTime<Tz>>

Makes a new value with the minute number changed.

fn with_second(&self, sec: u32) -> Option<DateTime<Tz>>

Makes a new value with the second number changed.

fn with_nanosecond(&self, nano: u32) -> Option<DateTime<Tz>>

Makes a new value with nanoseconds since the whole non-leap second changed.

fn hour12(&self) -> (bool, u32)

Returns the hour number from 1 to 12 with a boolean flag, which is false for AM and true for PM.

fn num_seconds_from_midnight(&self) -> u32

Returns the number of non-leap seconds past the last midnight.

impl<Tz: TimeZone> Copy for DateTime<Tz>where
    <Tz as TimeZone>::Offset: Copy,

impl<Tz: TimeZone> Eq for DateTime<Tz>

impl<Tz: TimeZone> Send for DateTime<Tz>where
    <Tz as TimeZone>::Offset: Send,