php-doc-en/reference/datetime/datetimeimmutable/createfromformat.xml

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<?xml version="1.0" encoding="utf-8"?>
<!-- $Revision$ -->
<refentry xml:id="datetimeimmutable.createfromformat" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
<refnamediv>
<refname>DateTimeImmutable::createFromFormat</refname>
<refname>date_create_immutable_from_format</refname>
<refpurpose>Parses a time string according to a specified format</refpurpose>
</refnamediv>
<refsect1 role="description">
&reftitle.description;
<para>&style.oop;</para>
<methodsynopsis role="oop">
<modifier>public</modifier> <modifier>static</modifier> <type class="union"><type>DateTimeImmutable</type><type>false</type></type><methodname>DateTimeImmutable::createFromFormat</methodname>
<methodparam><type>string</type><parameter>format</parameter></methodparam>
<methodparam><type>string</type><parameter>datetime</parameter></methodparam>
<methodparam choice="opt"><type class="union"><type>DateTimeZone</type><type>null</type></type><parameter>timezone</parameter><initializer>&null;</initializer></methodparam>
</methodsynopsis>
<para>&style.procedural;</para>
<methodsynopsis role="procedural">
<type class="union"><type>DateTimeImmutable</type><type>false</type></type><methodname>date_create_immutable_from_format</methodname>
<methodparam><type>string</type><parameter>format</parameter></methodparam>
<methodparam><type>string</type><parameter>datetime</parameter></methodparam>
<methodparam choice="opt"><type class="union"><type>DateTimeZone</type><type>null</type></type><parameter>timezone</parameter><initializer>&null;</initializer></methodparam>
</methodsynopsis>
<para>
Returns a new DateTimeImmutable object representing the date and time specified by the
<parameter>datetime</parameter> string, which was formatted in the given
<parameter>format</parameter>.
</para>
</refsect1>
<refsect1 role="parameters">
&reftitle.parameters;
<variablelist>
<varlistentry>
<term><parameter>format</parameter></term>
<listitem>
<para>
The format that the passed in <type>string</type> should be in. See the
formatting options below. In most cases, the same letters as for the
<function>date</function> can be used.
</para>
<para>
The format is parsed from left to right, which means that in some
situations the order in which the format characters are present effects
the result. In the case of <literal>z</literal> (the day of the year),
it is required that a year has already been parsed,
for example through the <literal>Y</literal> or <literal>y</literal>
characters.
</para>
<para>
Letters that are used for parsing numbers allow a wide range of values,
outside of what the logical range would be. For example, the
<literal>d</literal> (day of the month) accepts values in the range from
<literal>00</literal> to <literal>99</literal>. The only constraint is
on the amount of digits. The date/time parser's overflow mechanism is
used when out-of-range values are given. The examples below show some of
this behaviour.
</para>
<para>
<table>
<title>The following characters are recognized in the
<parameter>format</parameter> parameter string</title>
<tgroup cols="3">
<thead>
<row>
<entry><parameter>format</parameter> character</entry>
<entry>Description</entry>
<entry>Example parsable values</entry>
</row>
</thead>
<tbody>
<row>
<entry align="center"><emphasis>Day</emphasis></entry>
<entry>---</entry>
<entry>---</entry>
</row>
<row>
<entry><literal>d</literal> and <literal>j</literal></entry>
<entry>Day of the month, 2 digits with or without leading zeros</entry>
<entry>
<literal>01</literal> to <literal>31</literal> or
<literal>1</literal> to <literal>31</literal>. (2 digit numbers
higher than the number of days in the month are accepted, in which
case they will make the month overflow. For example using 33 with
January, means February 2nd)
</entry>
</row>
<row>
<entry><literal>D</literal> and <literal>l</literal></entry>
<entry>A textual representation of a day</entry>
<entry>
<literal>Mon</literal> through <literal>Sun</literal> or
<literal>Sunday</literal> through <literal>Saturday</literal>. If
the day name given is different then the day name belonging to a
parsed (or default) date is different, then an overflow occurs to
the <emphasis>next</emphasis> date with the given day name. See the
examples below for an explanation.
</entry>
</row>
<row>
<entry><literal>S</literal></entry>
<entry>English ordinal suffix for the day of the month, 2
characters. It's ignored while processing.</entry>
<entry>
<literal>st</literal>, <literal>nd</literal>, <literal>rd</literal> or
<literal>th</literal>.
</entry>
</row>
<row>
<entry><literal>z</literal></entry>
<entry>
The day of the year (starting from 0);
must be preceded by <literal>Y</literal> or <literal>y</literal>.
</entry>
<entry>
<literal>0</literal> through <literal>365</literal>. (3 digit
numbers higher than the numbers in a year are accepted, in which
case they will make the year overflow. For example using 366 with
2022, means January 2nd, 2023)
</entry>
</row>
<row>
<entry align="center"><emphasis>Month</emphasis></entry>
<entry>---</entry>
<entry>---</entry>
</row>
<row>
<entry><literal>F</literal> and <literal>M</literal></entry>
<entry>A textual representation of a month, such as January or Sept</entry>
<entry>
<literal>January</literal> through <literal>December</literal> or
<literal>Jan</literal> through <literal>Dec</literal>
</entry>
</row>
<row>
<entry><literal>m</literal> and <literal>n</literal></entry>
<entry>Numeric representation of a month, with or without leading zeros</entry>
<entry>
<literal>01</literal> through <literal>12</literal> or
<literal>1</literal> through <literal>12</literal>.
(2 digit numbers higher than 12 are accepted, in which case they
will make the year overflow. For example using 13 means January in
the next year)
</entry>
</row>
<row>
<entry align="center"><emphasis>Year</emphasis></entry>
<entry>---</entry>
<entry>---</entry>
</row>
<row>
<entry><literal>Y</literal></entry>
<entry>A full numeric representation of a year, up to 4 digits</entry>
<entry>Examples: <literal>0055</literal>, <literal>787</literal>,
<literal>1999</literal>, <literal>2003</literal></entry>
</row>
<row>
<entry><literal>y</literal></entry>
<entry>
A two digit representation of a year (which is assumed to be in the
range 1970-2069, inclusive)
</entry>
<entry>
Examples:
<literal>99</literal> or <literal>03</literal>
(which will be interpreted as <literal>1999</literal> and
<literal>2003</literal>, respectively)
</entry>
</row>
<row>
<entry align="center"><emphasis>Time</emphasis></entry>
<entry>---</entry>
<entry>---</entry>
</row>
<row>
<entry><literal>a</literal> and <literal>A</literal></entry>
<entry>Ante meridiem and Post meridiem</entry>
<entry><literal>am</literal> or <literal>pm</literal></entry>
</row>
<row>
<entry><literal>g</literal> and <literal>h</literal></entry>
<entry>12-hour format of an hour with or without leading zero</entry>
<entry>
<literal>1</literal> through <literal>12</literal> or
<literal>01</literal> through <literal>12</literal> (2 digit
numbers higher than 12 are accepted, in which case they will make
the day overflow. For example using <literal>14</literal> means
<literal>02</literal> in the next AM/PM period)
</entry>
</row>
<row>
<entry><literal>G</literal> and <literal>H</literal></entry>
<entry>24-hour format of an hour with or without leading zeros</entry>
<entry>
<literal>0</literal> through <literal>23</literal> or
<literal>00</literal> through <literal>23</literal> (2 digit
numbers higher than 24 are accepted, in which case they will make
the day overflow. For example using <literal>26</literal> means
<literal>02:00</literal> the next day)
</entry>
</row>
<row>
<entry><literal>i</literal></entry>
<entry>Minutes with leading zeros</entry>
<entry>
<literal>00</literal> to <literal>59</literal>. (2 digit
numbers higher than 59 are accepted, in which case they will make
the hour overflow. For example using <literal>66</literal> means
<literal>:06</literal> the next hour)
</entry>
</row>
<row>
<entry><literal>s</literal></entry>
<entry>Seconds, with leading zeros</entry>
<entry>
<literal>00</literal> through <literal>59</literal> (2 digit
numbers higher than 59 are accepted, in which case they will make
the minute overflow. For example using <literal>90</literal> means
<literal>:30</literal> the next minute)
</entry>
</row>
<row>
<entry><literal>v</literal></entry>
<entry>Fraction in milliseconds (up to three digits)</entry>
<entry>Example: <literal>12</literal> (<literal>0.12</literal>
seconds), <literal>345</literal> (<literal>0.345</literal> seconds)</entry>
</row>
<row>
<entry><literal>u</literal></entry>
<entry>Fraction in microseconds (up to six digits)</entry>
<entry>Example: <literal>45</literal> (<literal>0.45</literal>
seconds), <literal>654321</literal> (<literal>0.654321</literal>
seconds)</entry>
</row>
<row>
<entry align="center"><emphasis>Timezone</emphasis></entry>
<entry>---</entry>
<entry>---</entry>
</row>
<row>
<entry>
<literal>e</literal>, <literal>O</literal>,
<literal>P</literal> and <literal>T</literal>
</entry>
<entry>Timezone identifier, or difference to UTC in hours, or
difference to UTC with colon between hours and minutes, or timezone
abbreviation</entry>
<entry>Examples: <literal>UTC</literal>, <literal>GMT</literal>,
<literal>Atlantic/Azores</literal> or
<literal>+0200</literal> or <literal>+02:00</literal> or
<literal>EST</literal>, <literal>MDT</literal>
</entry>
</row>
<row>
<entry align="center"><emphasis>Full Date/Time</emphasis></entry>
<entry>---</entry>
<entry>---</entry>
</row>
<row>
<entry><literal>U</literal></entry>
<entry>Seconds since the Unix Epoch (January 1 1970 00:00:00 GMT)</entry>
<entry>Example: <literal>1292177455</literal></entry>
</row>
<row>
<entry align="center"><emphasis>Whitespace and Separators</emphasis></entry>
<entry>---</entry>
<entry>---</entry>
</row>
<row>
<entry><literal> </literal> (space)</entry>
<entry>One space or one tab</entry>
<entry>Example: <literal> </literal></entry>
</row>
<row>
<entry><literal>#</literal></entry>
<entry>
One of the following separation symbol: <literal>;</literal>,
<literal>:</literal>, <literal>/</literal>, <literal>.</literal>,
<literal>,</literal>, <literal>-</literal>, <literal>(</literal> or
<literal>)</literal>
</entry>
<entry>Example: <literal>/</literal></entry>
</row>
<row>
<entry>
<literal>;</literal>,
<literal>:</literal>, <literal>/</literal>, <literal>.</literal>,
<literal>,</literal>, <literal>-</literal>, <literal>(</literal> or
<literal>)</literal>
</entry>
<entry>The specified character.</entry>
<entry>Example: <literal>-</literal></entry>
</row>
<row>
<entry><literal>?</literal></entry>
<entry>A random byte</entry>
<entry>Example: <literal>^</literal> (Be aware that for UTF-8
characters you might need more than one <literal>?</literal>.
In this case, using <literal>*</literal> is probably what you want
instead)</entry>
</row>
<row>
<entry><literal>*</literal></entry>
<entry>Random bytes until the next separator or digit</entry>
<entry>Example: <literal>*</literal> in <literal>Y-*-d</literal> with
the string <literal>2009-aWord-08</literal> will match
<literal>aWord</literal></entry>
</row>
<row>
<entry><literal>!</literal></entry>
<entry>Resets all fields (year, month, day, hour, minute, second,
fraction and timezone information) to zero-like values (
<literal>0</literal> for hour, minute, second and fraction,
<literal>1</literal> for month and day, <literal>1970</literal>
for year and <literal>UTC</literal> for timezone information)</entry>
<entry>Without <literal>!,</literal> all fields will be set to the
current date and time.</entry>
</row>
<row>
<entry><literal>|</literal></entry>
<entry>Resets all fields (year, month, day, hour, minute, second,
fraction and timezone information) to zero-like values if they have
not been parsed yet</entry>
<entry><literal>Y-m-d|</literal> will set the year, month and day
to the information found in the string to parse, and sets the hour,
minute and second to 0.</entry>
</row>
<row>
<entry><literal>+</literal></entry>
<entry>If this format specifier is present, trailing data in the
string will not cause an error, but a warning instead</entry>
<entry>Use <methodname>DateTimeImmutable::getLastErrors</methodname> to find out
whether trailing data was present.</entry>
</row>
</tbody>
</tgroup>
</table>
</para>
<para>
Unrecognized characters in the format string will cause the
parsing to fail and an error message is appended to the returned
structure. You can query error messages with
<methodname>DateTimeImmutable::getLastErrors</methodname>.
</para>
<para>
To include literal characters in <parameter>format</parameter>, you have
to escape them with a backslash (<literal>\</literal>).
</para>
<para>
If <parameter>format</parameter> does not contain the character
<literal>!</literal> then portions of the generated date/time which are not
specified in <parameter>format</parameter> will be set to the current
system time.
</para>
<para>
If <parameter>format</parameter> contains the
character <literal>!</literal>, then portions of the generated
date/time not provided in <parameter>format</parameter>, as well as
values to the left-hand side of the <literal>!</literal>, will
be set to corresponding values from the Unix epoch.
</para>
<para>
If any time character is parsed, then all other time-related fields are
set to "0", unless also parsed.
</para>
<para>
The Unix epoch is 1970-01-01 00:00:00 UTC.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>datetime</parameter></term>
<listitem>
<para>
String representing the time.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>timezone</parameter></term>
<listitem>
<para>
A <classname>DateTimeZone</classname> object representing the
desired time zone.
</para>
<para>
If <parameter>timezone</parameter> is omitted or &null; and
<parameter>datetime</parameter> contains no timezone,
the current timezone will be used.
</para>
<note>
<para>
The <parameter>timezone</parameter> parameter
and the current timezone are ignored when the
<parameter>datetime</parameter> parameter either
contains a UNIX timestamp (e.g. <literal>946684800</literal>)
or specifies a timezone
(e.g. <literal>2010-01-28T15:00:00+02:00</literal>).
</para>
</note>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1 role="returnvalues">
&reftitle.returnvalues;
<para>
Returns a new DateTimeImmutable instance&return.falseforfailure;.
</para>
</refsect1>
<refsect1 role="changelog">
&reftitle.changelog;
<para>
<informaltable>
<tgroup cols="2">
<thead>
<row>
<entry>&Version;</entry>
<entry>&Description;</entry>
</row>
</thead>
<tbody>
<row>
<entry>7.3.0</entry>
<entry>
The <literal>v</literal> <parameter>format</parameter> specifier has been added.
</entry>
</row>
</tbody>
</tgroup>
</informaltable>
</para>
</refsect1>
<refsect1 role="examples">
&reftitle.examples;
<example>
<title><function>DateTimeImmutable::createFromFormat</function> example</title>
<para>&style.oop;</para>
<programlisting role="php">
<![CDATA[
<?php
$date = DateTimeImmutable::createFromFormat('j-M-Y', '15-Feb-2009');
echo $date->format('Y-m-d');
?>
]]>
</programlisting>
</example>
<example>
<title>Intricacies of <function>DateTimeImmutable::createFromFormat</function></title>
<programlisting role="php">
<![CDATA[
<?php
echo 'Current time: ' . date('Y-m-d H:i:s') . "\n";
$format = 'Y-m-d';
$date = DateTimeImmutable::createFromFormat($format, '2009-02-15');
echo "Format: $format; " . $date->format('Y-m-d H:i:s') . "\n";
$format = 'Y-m-d H:i:s';
$date = DateTimeImmutable::createFromFormat($format, '2009-02-15 15:16:17');
echo "Format: $format; " . $date->format('Y-m-d H:i:s') . "\n";
$format = 'Y-m-!d H:i:s';
$date = DateTimeImmutable::createFromFormat($format, '2009-02-15 15:16:17');
echo "Format: $format; " . $date->format('Y-m-d H:i:s') . "\n";
$format = '!d';
$date = DateTimeImmutable::createFromFormat($format, '15');
echo "Format: $format; " . $date->format('Y-m-d H:i:s') . "\n";
$format = 'i';
$date = DateTimeImmutable::createFromFormat($format, '15');
echo "Format: $format; " . $date->format('Y-m-d H:i:s') . "\n";
?>
]]>
</programlisting>
&example.outputs.similar;
<screen>
<![CDATA[
Current time: 2022-06-02 15:50:46
Format: Y-m-d; 2009-02-15 15:50:46
Format: Y-m-d H:i:s; 2009-02-15 15:16:17
Format: Y-m-!d H:i:s; 1970-01-15 15:16:17
Format: !d; 1970-01-15 00:00:00
Format: i; 2022-06-02 00:15:00
]]>
</screen>
</example>
<example>
<title>Format string with literal characters</title>
<programlisting role="php">
<![CDATA[
<?php
echo DateTimeImmutable::createFromFormat('H\h i\m s\s','23h 15m 03s')->format('H:i:s');
?>
]]>
</programlisting>
&example.outputs.similar;
<screen>
<![CDATA[
23:15:03
]]>
</screen>
</example>
<example>
<title>Overflow behaviour</title>
<programlisting role="php">
<![CDATA[
<?php
echo DateTimeImmutable::createFromFormat('Y-m-d H:i:s', '2021-17-35 16:60:97')->format(DateTimeImmutable::RFC2822);
?>
]]>
</programlisting>
&example.outputs.similar;
<screen>
<![CDATA[
Sat, 04 Jun 2022 17:01:37 +0000
]]>
</screen>
<para>
Although the result looks odd, it is correct, as the following overflows
happen:
</para>
<orderedlist>
<listitem>
<simpara>
<literal>97</literal> seconds overflows to <literal>1</literal> minute,
leaving <literal>37</literal> seconds.
</simpara>
</listitem>
<listitem>
<simpara>
<literal>61</literal> minutes overflows to <literal>1</literal> hour,
leaving <literal>1</literal> minutes.
</simpara>
</listitem>
<listitem>
<simpara>
<literal>35</literal> days overflows to <literal>1</literal> month,
leaving <literal>4</literal> days. The amount of days that are left over
depends on the month, as not every month has the same amount of days.
</simpara>
</listitem>
<listitem>
<simpara>
<literal>18</literal> months overflows to <literal>1</literal> year,
leaving <literal>6</literal> months.
</simpara>
</listitem>
</orderedlist>
</example>
<example>
<title>Overflowing day name behaviour</title>
<programlisting role="php">
<![CDATA[
<?php
$d = DateTime::createFromFormat(DateTimeInterface::RFC1123, 'Mon, 3 Aug 2020 25:00:00 +0000');
echo $d->format(DateTime::RFC1123), "\n";
?>
]]>
</programlisting>
&example.outputs.similar;
<screen>
<![CDATA[
Mon, 10 Aug 2020 01:00:00 +0000
]]>
</screen>
<para>
Although the result looks odd, it is correct, as the following overflows
happen:
</para>
<orderedlist>
<listitem>
<simpara>
<literal>3 Aug 2020 25:00:00</literal> overflows to <literal>(Tue) 4 Aug
2020 01:00</literal>.
</simpara>
</listitem>
<listitem>
<simpara>
<literal>Mon</literal> gets applied, which advances the date to
<literal>Mon, 10 Aug 2020 01:00:00</literal>. The explanation of
relative keywords such as <literal>Mon</literal> is explained in the
section on <link linkend="datetime.formats.relative">relative
formats</link>.
</simpara>
</listitem>
</orderedlist>
</example>
<para>
In order to detect overflows in dates, you can use the
<methodname>DateTimeImmutable::getLastErrors</methodname> name, which will
include a warning if an overflow occured.
</para>
<example>
<title>Detecting overflown dates</title>
<programlisting role="php">
<![CDATA[
<?php
$d = DateTimeImmutable::createFromFormat('Y-m-d H:i:s', '2021-17-35 16:60:97');
echo $d->format(DateTimeImmutable::RFC2822), "\n\n";
var_dump(DateTimeImmutable::GetLastErrors());
?>
]]>
</programlisting>
&example.outputs.similar;
<screen>
<![CDATA[
Sat, 04 Jun 2022 17:01:37 +0000
array(4) {
'warning_count' =>
int(2)
'warnings' =>
array(1) {
[19] =>
string(27) "The parsed date was invalid"
}
'error_count' =>
int(0)
'errors' =>
array(0) {
}
}
]]>
</screen>
</example>
</refsect1>
<refsect1 role="seealso">
&reftitle.seealso;
<simplelist>
<member><function>DateTimeImmutable::__construct</function></member>
<member><function>DateTimeImmutable::getLastErrors</function></member>
<member><function>checkdate</function></member>
<member><function>strptime</function></member>
</simplelist>
</refsect1>
</refentry>
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