On 4 April 2011 16:35, Ian php_l...@fishnet.co.uk wrote:
Hi,
I have a problem using the php built in classes DateTime and DateTimeZone.
The idea behind the following code is to return the timestamp for the
current time in Singapore (or other places). What it actually returns
is the timestamp for the local system. Other formatted dates appear to
return correctly, which is why I am puzzled.
I am using the latest php 5.3.6 compiled from source on a OpenVZ CentOS
container. All packages are up to date.
Am I doing something wrong or is this a bug?
I can workaround this problem my parsing the correctly formatted date
using strtotime() but I would like to know what's going on.
This is the output of the script:
Current time in Asia/Singapore is 2011-04-04 23:32:36
Timestamp for Asia/Singapore is 1301931156
Date created from previous timestamp is 2011-04-04 16:32:36
The code is :
?php
$timezone=Asia/Singapore;
# Create Timezone object
$remote_timezone = new DateTimeZone($timezone);
# Create datetime object
$remote_time = new DateTime(now , $remote_timezone);
# Print the date
print Current time in {$timezone} ;
print is {$remote_time-format(Y-m-d H:i:s)}br/;
# Print the timestamp
print Timestamp for {$timezone} ;
print is {$remote_time-format(U)}br /;
# Get the timestamp and create a date from it
$timestamp = (int)$remote_time-format(U);
# Show the formatted date created from timestamp
print Date created from previous timestamp is ;
print date(Y-m-d H:i:s,$timestamp).br/;
?
Timestamps (the integer value) do not hold the timezone data.
Internally, the value represents a number of milliseconds from a point
in time.
So saying timestamp for Asia/Singapore isn't right. It is just Timestamp.
The following script (http://pastebin.com/0MQAaYUq) may show you in a
more concrete way ...
?php
$a_Times = array(
'now',
'2011-03-27 00:59:59',
'2011-03-27 02:00:00',
);
// Create Timezone objects
$a_Timezones = array(
'Singapore' = new DateTimeZone('Asia/Singapore'),
'NewYork ' = new DateTimeZone('America/New_York'),
'London ' = new DateTimeZone('Europe/London'),
'UTC ' = new DateTimeZone('UTC'),
);
foreach($a_Times as $s_Time) {
echo 'Time : ', $s_Time, PHP_EOL;
// Create datetime objects
$a_DateTimes = array();
foreach($a_Timezones as $s_Timezone = $tz_Timezone) {
$a_DateTimes[$s_Timezone] = new DateTime($s_Time ,
$tz_Timezone);
}
// Print the date
foreach($a_DateTimes as $s_Timezone = $dt_DateTime) {
echo
'Current time in ', $s_Timezone, ' : ',
$dt_DateTime-format(DateTime::RSS),
' Offset : ', str_pad($dt_DateTime-getOffset(), 6, '
', STR_PAD_LEFT),
' Timestamp : ', ($i_Timestamp =
$dt_DateTime-getTimestamp()),
' Local : ', date(DateTime::RSS, $i_Timestamp),
PHP_EOL;
}
echo PHP_EOL;
}
?
outputs (http://pastebin.com/mETSbR7h) ...
Time : now
Current time in Singapore : Tue, 05 Apr 2011 17:56:32 +0800 Offset :
28800 Timestamp : 1301997392 Local : Tue, 05 Apr 2011 10:56:32
+0100
Current time in NewYork : Tue, 05 Apr 2011 05:56:32 -0400 Offset :
-14400 Timestamp : 1301997392 Local : Tue, 05 Apr 2011 10:56:32
+0100
Current time in London: Tue, 05 Apr 2011 10:56:32 +0100 Offset :
3600 Timestamp : 1301997392 Local : Tue, 05 Apr 2011 10:56:32
+0100
Current time in UTC : Tue, 05 Apr 2011 09:56:32 + Offset :
0 Timestamp : 1301997392 Local : Tue, 05 Apr 2011 10:56:32
+0100
Time : 2011-03-27 00:59:59
Current time in Singapore : Sun, 27 Mar 2011 00:59:59 +0800 Offset :
28800 Timestamp : 1301158799 Local : Sat, 26 Mar 2011 16:59:59
+
Current time in NewYork : Sun, 27 Mar 2011 00:59:59 -0400 Offset :
-14400 Timestamp : 1301201999 Local : Sun, 27 Mar 2011 05:59:59
+0100
Current time in London: Sun, 27 Mar 2011 00:59:59 + Offset :
0 Timestamp : 1301187599 Local : Sun, 27 Mar 2011 00:59:59
+
Current time in UTC : Sun, 27 Mar 2011 00:59:59 + Offset :
0 Timestamp : 1301187599 Local : Sun, 27 Mar 2011 00:59:59
+
Time : 2011-03-27 02:00:00
Current time in Singapore : Sun, 27 Mar 2011 02:00:00 +0800 Offset :
28800 Timestamp : 1301162400 Local : Sat, 26 Mar 2011 18:00:00
+
Current time in NewYork : Sun, 27 Mar 2011 02:00:00 -0400 Offset :
-14400 Timestamp : 1301205600 Local : Sun, 27 Mar 2011 07:00:00
+0100
Current time in London: Sun, 27 Mar 2011 02:00:00 +0100 Offset :
3600 Timestamp : 1301187600 Local : Sun, 27 Mar 2011 02:00:00
+0100
Current time in UTC : Sun, 27 Mar 2011 02:00:00 + Offset :
0 Timestamp : 1301191200 Local : Sun, 27 Mar 2011 03:00:00
+0100
Getting the the timestamp for a DateTime object
