PHP 5 Date/Time Functions
PHP Date/Time Introduction
The date/time functions allow you to get the date and time from the server where your PHP script runs. You can then use the date/time functions to format the date and time in several ways.
Note: These functions depend on the locale settings of your server. Remember to take daylight saving time and leap years into consideration when working with these functions.
Installation
The PHP date/time functions are part of the PHP core. No installation is required to use these functions.
Runtime Configuration
The behavior of these functions is affected by settings in php.ini:
| Name | Description | Default | PHP Version | 
|---|---|---|---|
| date.timezone | The default timezone (used by all date/time functions) | "" | PHP 5.1 | 
| date.default_latitude | The default latitude (used by date_sunrise() and date_sunset()) | "31.7667" | PHP 5.0 | 
| date.default_longitude | The default longitude (used by date_sunrise() and date_sunset()) | "35.2333" | PHP 5.0 | 
| date.sunrise_zenith | The default sunrise zenith (used by date_sunrise() and date_sunset()) | "90.83" | PHP 5.0 | 
| date.sunset_zenith | The default sunset zenith (used by date_sunrise() and date_sunset()) | "90.83" | PHP 5.0 | 
PHP 5 Date/Time Functions
| Function | Description | 
|---|---|
| checkdate() | Validates a Gregorian date | 
| date_add() | Adds days, months, years, hours, minutes, and seconds to a date | 
| date_create_from_format() | Returns a new DateTime object formatted according to a specified format | 
| date_create() | Returns a new DateTime object | 
| date_date_set() | Sets a new date | 
| date_default_timezone_get() | Returns the default timezone used by all date/time functions | 
| date_default_timezone_set() | Sets the default timezone used by all date/time functions | 
| date_diff() | Returns the difference between two dates | 
| date_format() | Returns a date formatted according to a specified format | 
| date_get_last_errors() | Returns the warnings/errors found in a date string | 
| date_interval_create_from_date_string() | Sets up a DateInterval from the relative parts of the string | 
| date_interval_format() | Formats the interval | 
| date_isodate_set() | Sets the ISO date | 
| date_modify() | Modifies the timestamp | 
| date_offset_get() | Returns the timezone offset | 
| date_parse_from_format() | Returns an associative array with detailed info about a specified date, according to a specified format | 
| date_parse() | Returns an associative array with detailed info about a specified date | 
| date_sub() | Subtracts days, months, years, hours, minutes, and seconds from a date | 
| date_sun_info() | Returns an array containing info about sunset/sunrise and twilight begin/end, for a specified day and location | 
| date_sunrise() | Returns the sunrise time for a specified day and location | 
| date_sunset() | Returns the sunset time for a specified day and location | 
| date_time_set() | Sets the time | 
| date_timestamp_get() | Returns the Unix timestamp | 
| date_timestamp_set() | Sets the date and time based on a Unix timestamp | 
| date_timezone_get() | Returns the time zone of the given DateTime object | 
| date_timezone_set() | Sets the time zone for the DateTime object | 
| date() | Formats a local date and time | 
| getdate() | Returns date/time information of a timestamp or the current local date/time | 
| gettimeofday() | Returns the current time | 
| gmdate() | Formats a GMT/UTC date and time | 
| gmmktime() | Returns the Unix timestamp for a GMT date | 
| gmstrftime() | Formats a GMT/UTC date and time according to locale settings | 
| idate() | Formats a local time/date as integer | 
| localtime() | Returns the local time | 
| microtime() | Returns the current Unix timestamp with microseconds | 
| mktime() | Returns the Unix timestamp for a date | 
| strftime() | Formats a local time and/or date according to locale settings | 
| strptime() | Parses a time/date generated with strftime() | 
| strtotime() | Parses an English textual datetime into a Unix timestamp | 
| time() | Returns the current time as a Unix timestamp | 
| timezone_abbreviations_list() | Returns an associative array containing dst, offset, and the timezone name | 
| timezone_identifiers_list() | Returns an indexed array with all timezone identifiers | 
| timezone_location_get() | Returns location information for a specified timezone | 
| timezone_name_from_ abbr() | Returns the timezone name from abbreviation | 
| timezone_name_get() | Returns the name of the timezone | 
| timezone_offset_get() | Returns the timezone offset from GMT | 
| timezone_open() | Creates new DateTimeZone object | 
| timezone_transitions_get() | Returns all transitions for the timezone | 
| timezone_version_get() | Returns the version of the timezone db | 
PHP 5 Predefined Date/Time Constants
| Constant | Description | 
|---|---|
| DATE_ATOM | Atom (example: 2005-08-15T16:13:03+0000) | 
| DATE_COOKIE | HTTP Cookies (example: Sun, 14 Aug 2005 16:13:03 UTC) | 
| DATE_ISO8601 | ISO-8601 (example: 2005-08-14T16:13:03+0000) | 
| DATE_RFC822 | RFC 822 (example: Sun, 14 Aug 2005 16:13:03 UTC) | 
| DATE_RFC850 | RFC 850 (example: Sunday, 14-Aug-05 16:13:03 UTC) | 
| DATE_RFC1036 | RFC 1036 (example: Sunday, 14-Aug-05 16:13:03 UTC) | 
| DATE_RFC1123 | RFC 1123 (example: Sun, 14 Aug 2005 16:13:03 UTC) | 
| DATE_RFC2822 | RFC 2822 (Sun, 14 Aug 2005 16:13:03 +0000) | 
| DATE_RSS | RSS (Sun, 14 Aug 2005 16:13:03 UTC) | 
| DATE_W3C | World Wide Web Consortium (example: 2005-08-14T16:13:03+0000) | 

