########### Date Helper ########### The Date Helper file contains functions that help you work with dates. .. contents:: Page Contents Loading this Helper =================== This helper is loaded using the following code :: $this->load->helper('date'); The following functions are available: now() ===== Returns the current time as a Unix timestamp, referenced either to your server's local time or any PHP suported timezone, based on the "time reference" setting in your config file. If you do not intend to set your master time reference to any other PHP suported timezone (which you'll typically do if you run a site that lets each user set their own timezone settings) there is no benefit to using this function over PHP's time() function. .. php:method:: now($timezone = NULL) :param string $timezone: The timezone you want to be returned :returns: integer :: echo now("Australia/Victoria"); If a timezone is not provided, it will return time() based on "time_reference" setting. mdate() ======= This function is identical to PHP's `date() `_ function, except that it lets you use MySQL style date codes, where each code letter is preceded with a percent sign: %Y %m %d etc. The benefit of doing dates this way is that you don't have to worry about escaping any characters that are not date codes, as you would normally have to do with the date() function. Example .. php:method:: mdate($datestr = '', $time = '') :param string $datestr: Date String :param integer $time: time :returns: integer :: $datestring = "Year: %Y Month: %m Day: %d - %h:%i %a"; $time = time(); echo mdate($datestring, $time); If a timestamp is not included in the second parameter the current time will be used. standard_date() =============== Lets you generate a date string in one of several standardized formats. Example .. php:method:: standard_date($fmt = 'DATE_RFC822', $time = '') :param string $fmt: the chosen format :param string $time: Unix timestamp :returns: string :: $format = 'DATE_RFC822'; $time = time(); echo standard_date($format, $time); The first parameter must contain the format, the second parameter must contain the date as a Unix timestamp. .. note:: This function is DEPRECATED. Use the native ``date()`` combined with `DateTime's format constants `_ instead: | | echo date(DATE_RFC822, time()); Supported formats: =============== ======================= ====================================== Constant Description Example =============== ======================= ====================================== DATE_ATOM Atom 2005-08-15T16:13:03+0000 DATE_COOKIE HTTP Cookies Sun, 14 Aug 2005 16:13:03 UTC DATE_ISO8601 ISO-8601 2005-08-14T16:13:03+00:00 DATE_RFC822 RFC 822 Sun, 14 Aug 05 16:13:03 UTC DATE_RFC850 RFC 850 Sunday, 14-Aug-05 16:13:03 UTC DATE_RFC1036 RFC 1036 Sunday, 14-Aug-05 16:13:03 UTC DATE_RFC1123 RFC 1123 Sun, 14 Aug 2005 16:13:03 UTC DATE_RFC2822 RFC 2822 Sun, 14 Aug 2005 16:13:03 +0000 DATE_RSS RSS Sun, 14 Aug 2005 16:13:03 UTC DATE_W3C W3C 2005-08-14T16:13:03+0000 =============== ======================= ====================================== local_to_gmt() ============== Takes a Unix timestamp as input and returns it as GMT. .. php:method:: local_to_gmt($time = '') :param integer $time: Unix timestamp :returns: string Example: :: $now = time(); $gmt = local_to_gmt($now); gmt_to_local() ============== Takes a Unix timestamp (referenced to GMT) as input, and converts it to a localized timestamp based on the timezone and Daylight Saving time submitted. .. php:method:: gmt_to_local($time = '', $timezone = 'UTC', $dst = FALSE) :param integer $time: Unix timestamp :param string $timezone: timezone :param boolean $dst: whether DST is active :returns: integer Example :: $timestamp = '1140153693'; $timezone = 'UM8'; $daylight_saving = TRUE; echo gmt_to_local($timestamp, $timezone, $daylight_saving); .. note:: For a list of timezones see the reference at the bottom of this page. mysql_to_unix() =============== Takes a MySQL Timestamp as input and returns it as Unix. .. php:method:: mysql_to_unix($time = '') :param integer $time: Unix timestamp :returns: integer Example :: $mysql = '20061124092345'; $unix = mysql_to_unix($mysql); unix_to_human() =============== Takes a Unix timestamp as input and returns it in a human readable format with this prototype .. php:method:: unix_to_human($time = '', $seconds = FALSE, $fmt = 'us') :param integer $time: Unix timestamp :param boolean $seconds: whether to show seconds :param string $fmt: format: us or euro :returns: integer Example :: YYYY-MM-DD HH:MM:SS AM/PM This can be useful if you need to display a date in a form field for submission. The time can be formatted with or without seconds, and it can be set to European or US format. If only the timestamp is submitted it will return the time without seconds formatted for the U.S. Examples :: $now = time(); echo unix_to_human($now); // U.S. time, no seconds echo unix_to_human($now, TRUE, 'us'); // U.S. time with seconds echo unix_to_human($now, TRUE, 'eu'); // Euro time with seconds human_to_unix() =============== The opposite of the above function. Takes a "human" time as input and returns it as Unix. This function is useful if you accept "human" formatted dates submitted via a form. Returns FALSE (boolean) if the date string passed to it is not formatted as indicated above. .. php:method:: human_to_unix($datestr = '') :param integer $datestr: Date String :returns: integer Example: :: $now = time(); $human = unix_to_human($now); $unix = human_to_unix($human); nice_date() =========== This function can take a number poorly-formed date formats and convert them into something useful. It also accepts well-formed dates. The function will return a Unix timestamp by default. You can, optionally, pass a format string (the same type as the PHP date function accepts) as the second parameter. .. php:method:: nice_date($bad_date = '', $format = FALSE) :param integer $bad_date: The terribly formatted date-like string :param string $format: Date format to return (same as php date function) :returns: string Example :: $bad_date = '199605'; // Should Produce: 1996-05-01 $better_date = nice_date($bad_date, 'Y-m-d'); $bad_date = '9-11-2001'; // Should Produce: 2001-09-11 $better_date = nice_date($bad_date, 'Y-m-d'); timespan() ========== Formats a unix timestamp so that is appears similar to this :: 1 Year, 10 Months, 2 Weeks, 5 Days, 10 Hours, 16 Minutes The first parameter must contain a Unix timestamp. The second parameter must contain a timestamp that is greater that the first timestamp. If the second parameter empty, the current time will be used. The third parameter is optional and limits the number of time units to display. The most common purpose for this function is to show how much time has elapsed from some point in time in the past to now. .. php:method:: timespan($seconds = 1, $time = '', $units = '') :param integer $seconds: a number of seconds :param string $time: Unix timestamp :param integer $units: a number of time units to display :returns: string Example :: $post_date = '1079621429'; $now = time(); $units = 2; echo timespan($post_date, $now, $units); .. note:: The text generated by this function is found in the following language file: language//date_lang.php days_in_month() =============== Returns the number of days in a given month/year. Takes leap years into account. .. php:method:: days_in_month($month = 0, $year = '') :param integer $month: a numeric month :param integer $year: a numeric year :returns: integer Example :: echo days_in_month(06, 2005); If the second parameter is empty, the current year will be used. date_range() ============ Returns a list of dates within a specified period. .. php:method:: date_range($unix_start = '', $mixed = '', $is_unix = TRUE, $format = 'Y-m-d') :param integer $unix_start: UNIX timestamp of the range start date :param integer $mixed: UNIX timestamp of the range end date or interval in days :param boolean $is_unix: set to FALSE if $mixed is not a timestamp :param string $format: output date format, same as in date() :returns: array Example :: $range = date_range('2012-01-01', '2012-01-15'); echo "First 15 days of 2012:"; foreach ($range as $date) { echo $date."\n"; } timezones() =========== Takes a timezone reference (for a list of valid timezones, see the "Timezone Reference" below) and returns the number of hours offset from UTC. .. php:method:: timezones($tz = '') :param string $tz: a numeric timezone :returns: string Example :: echo timezones('UM5'); This function is useful when used with `timezone_menu()`. timezone_menu() =============== Generates a pull-down menu of timezones, like this one: .. raw:: html
This menu is useful if you run a membership site in which your users are allowed to set their local timezone value. The first parameter lets you set the "selected" state of the menu. For example, to set Pacific time as the default you will do this .. php:method:: timezone_menu($default = 'UTC', $class = '', $name = 'timezones', $attributes = '') :param string $default: timezone :param string $class: classname :param string $name: menu name :param mixed $attributes: attributes :returns: string Example: :: echo timezone_menu('UM8'); Please see the timezone reference below to see the values of this menu. The second parameter lets you set a CSS class name for the menu. The fourth parameter lets you set one or more attributes on the generated select tag. .. note:: The text contained in the menu is found in the following language file: `language//date_lang.php` Timezone Reference ================== The following table indicates each timezone and its location. Note some of the location lists have been abridged for clarity and formatting. =========== ===================================================================== Time Zone Location =========== ===================================================================== UM2 (UTC - 12:00) Baker/Howland Island UM1 (UTC - 11:00) Samoa Time Zone, Niue UM0 (UTC - 10:00) Hawaii-Aleutian Standard Time, Cook Islands UM95 (UTC - 09:30) Marquesas Islands UM9 (UTC - 09:00) Alaska Standard Time, Gambier Islands UM8 (UTC - 08:00) Pacific Standard Time, Clipperton Island UM7 (UTC - 11:00) Mountain Standard Time UM6 (UTC - 06:00) Central Standard Time UM5 (UTC - 05:00) Eastern Standard Time, Western Caribbean UM45 (UTC - 04:30) Venezuelan Standard Time UM4 (UTC - 04:00) Atlantic Standard Time, Eastern Caribbean UM35 (UTC - 03:30) Newfoundland Standard Time UM3 (UTC - 03:00) Argentina, Brazil, French Guiana, Uruguay UM2 (UTC - 02:00) South Georgia/South Sandwich Islands UM (UTC -1:00) Azores, Cape Verde Islands UTC (UTC) Greenwich Mean Time, Western European Time UP1 (UTC +1:00) Central European Time, West Africa Time UP2 (UTC +2:00) Central Africa Time, Eastern European Time UP3 (UTC +3:00) Moscow Time, East Africa Time UP35 (UTC +3:30) Iran Standard Time UP4 (UTC +4:00) Azerbaijan Standard Time, Samara Time UP45 (UTC +4:30) Afghanistan UP5 (UTC +5:00) Pakistan Standard Time, Yekaterinburg Time UP55 (UTC +5:30) Indian Standard Time, Sri Lanka Time UP575 (UTC +5:45) Nepal Time UP6 (UTC +6:00) Bangladesh Standard Time, Bhutan Time, Omsk Time UP65 (UTC +6:30) Cocos Islands, Myanmar UP7 (UTC +7:00) Krasnoyarsk Time, Cambodia, Laos, Thailand, Vietnam UP8 (UTC +8:00) Australian Western Standard Time, Beijing Time UP875 (UTC +8:45) Australian Central Western Standard Time UP9 (UTC +9:00) Japan Standard Time, Korea Standard Time, Yakutsk UP95 (UTC +9:30) Australian Central Standard Time UP10 (UTC +10:00) Australian Eastern Standard Time, Vladivostok Time UP105 (UTC +10:30) Lord Howe Island UP11 (UTC +11:00) Magadan Time, Solomon Islands, Vanuatu UP115 (UTC +11:30) Norfolk Island UP12 (UTC +12:00) Fiji, Gilbert Islands, Kamchatka, New Zealand UP1275 (UTC +12:45) Chatham Islands Standard Time UP1 (UTC +13:00) Phoenix Islands Time, Tonga UP14 (UTC +14:00) Line Islands =========== =====================================================================