[SOLVED] timezone trouble

[jakebur01]

I am having trouble putting the puzzle together.

 

I have a form with timezone, hour, day, and year.

 

Ex. of time zone option:

   <option value="-7">GMT - 7 Hours (MOUNTAIN STANDARD TIME-USA-CANADA)</option>
		   <option value="-6">GMT - 6 Hours (CENTRAL STANDARD TIME-USA-CANADA)</option>
		   <option value="-5">GMT - 5 Hours (EASTERN STANDARD TIME-USA-CANADA)</option>
		   <option value="-4">GMT - 4 Hours (ATLANTIC STANDARD TIME)</option>
		   <option value="-3">GMT - 3 Hours</option>
		   <option value="-2">GMT - 2 Hours (AZORES TIME)</option>
		   <option value="-1">GMT - 1 Hours (WEST AFRICA TIME)</option>
		   <option value="+0">GMT (WESTERN EUROPEAN TIME)</option>

 

I am posting this to a page where I need to convert the time and date into a timestamp according to the timezone they chose.

 

Note: The server is sitting on central time zone.

 

$hour=$_POST['hour'];
$month=$_POST['month'];
$day=$_POST['day'];
$year=$_POST['year'];

$timezone=$_POST['timezone'];

$currenttimezone="-6";

$finalhour=

$timestamp = mktime($finalhour, 0, 0, $month, $day, $year);

 

I stopped..... I really don't know what I am doing here. My current timezone is -6(central time).

 

I am using this for a scheduled chat time. So if someone scheduled it for 2 pm china time, they would be able to access the chat at that time.

[revraz]

$finalhour=$hour - $currenttimezone;

 

But $currenttimezone needs to be a INT not a string.

[jakebur01]

I'm confused... $hour is the hour they selected in the form. $timezone is the time zone selection in the form(it holds values like -2, +4, 0, -3, etc.) And I was using $currenttimezone to get things back to greenwich mean time (that should be +6 not -6), I am 6 hours behind greenwich mean time.

[unkwntech]

Do all your calculations against GMT (0) then.

$currentTime = gmdate(H);//Timestamp for GMT
$timeZone = '-8' //My Time offset - Pacific Cost
$eventTime = $currentTime + $timeZone
echo $eventTime;

 

If I ran this now it should output 10, as it's 10:35 here, you'll have to expand on it for the minutes, but it's the same process.

 

EDIT: I fixed some logic errors

[redarrow]

wouldnt it be better useing the putenv function..............

 

<?php
echo "Original Time: ". date("h:i:s")."\n";
putenv("TZ=US/Eastern");
echo "New Time: ". date("h:i:s")."\n";
?>

[jakebur01]

I need to use the unix timestamp.

[unkwntech]

gmdate takes the same parameters as date so change it to gmdate('u') and you will get EPOCH for GMT.

[jakebur01]

I have a chat that users can schedule at a given time. In the form they are able to choose timezone, hour, day, and month.

 

I am storing this into my database as a unix time stamp.

 

What is the best way for me to do this?

 

    <form name="form1" method="post" action="process_meeting.php">
	  <table width="614" border="0" cellspacing="3" cellpadding="3">
            <tr>
              <td width="107" class="style23">Type:</td>
              <td width="222"><select name="select">
                <option value="t1">t1</option>
                <option value="t2">t2</option>
                <option value="t3">t3</option>
                <option value="t4">t4</option>
                <option value="t5">t5</option>
              </select>
              </td>
            </tr>
            <tr>
              <td class="style23">Club:</td>
              <td><input type="text" name="textfield"></td>
            </tr>
            <tr>
              <td class="style23">Topic:</td>
              <td><input type="text" name="textfield2"></td>
            </tr>
            <tr>
              <td class="style23">Timezone:</td>
              <td>
		  
		 <select name="timezone">
		   <option value="-12">GMT - 12 Hours (INTERNATIONAL DATE LINE WEST)</option>
		   <option value="-11">GMT - 11 Hours (NOME TIME)</option>
		   <option value="-10">GMT - 10 Hours (HAWAII/ALASKA STANDARD TIME)</option>
		   <option value="-9">GMT - 9 Hours (ALASKA/YUKON STANDARD TIME)</option>
		   <option value="-8">GMT - 8 Hours (PACIFIC STANDARD TIME-USA-CANADA)</option>
		   <option value="-7">GMT - 7 Hours (MOUNTAIN STANDARD TIME-USA-CANADA)</option>
		   <option value="-6">GMT - 6 Hours (CENTRAL STANDARD TIME-USA-CANADA)</option>
		   <option value="-5">GMT - 5 Hours (EASTERN STANDARD TIME-USA-CANADA)</option>
		   <option value="-4">GMT - 4 Hours (ATLANTIC STANDARD TIME)</option>
		   <option value="-3">GMT - 3 Hours</option>
		   <option value="-2">GMT - 2 Hours (AZORES TIME)</option>
		   <option value="-1">GMT - 1 Hours (WEST AFRICA TIME)</option>
		   <option value="+0">GMT (WESTERN EUROPEAN TIME)</option>
		   <option value="+1">GMT + 1 Hour (CENTRAL EUROPEAN TIME)</option>
		   <option value="+2">GMT + 2 Hours</option>
		   <option value="+3">GMT + 3 Hours</option>
		   <option value="+4">GMT + 4 Hours</option>
		   <option value="+5">GMT + 5 Hours</option>
		   <option value="+6">GMT + 6 Hours</option>
		   <option value="+7">GMT + 7 Hours</option>
		   <option value="+8">GMT + 8 Hours</option>
		   <option value="+9">GMT + 9 Hours</option>
		   <option value="+10">GMT + 10 Hours</option>
		   <option value="+11">GMT + 11 Hours</option>
		   <option value="+12">GMT + 12 Hours</option>
		 </select>
		  </td>
            </tr>
            <tr>
              <td class="style23">Hour:</td>
              <td><select name=hour>
<option value=00>00</option>
<option value=01>01</option>
<option value=02>02</option>
<option value=03>03</option>
<option value=04>04</option>
<option value=05>05</option>
<option value=06>06</option>

<option value=07>07</option>
<option value=08>08</option>
<option value=09>09</option>
<option value=10>10</option>
<option value=11>11</option>
<option value=12>12</option>
<option value=13>13</option>
<option value=14>14</option>
<option value=15>15</option>

<option value=16>16</option>
<option value=17>17</option>
<option value=18>18</option>
<option value=19>19</option>
<option value=20>20</option>
<option value=21>21</option>
<option value=22>22</option>
<option value=23>23</option>
<option value=24>24</option>

</select></td>
            </tr>
            <tr>
              <td class="style23">Month:</td>
              <td><select name=month value=''>Select Month</option>
<option value='01'>January</option>
<option value='02'>February</option>
<option value='03'>March</option>
<option value='04'>April</option>
<option value='05'>May</option>

<option value='06'>June</option>
<option value='07'>July</option>
<option value='08'>August</option>
<option value='09'>September</option>
<option value='10'>October</option>
<option value='11'>November</option>
<option value='12'>December</option>
</select>
</td>
            </tr>
            <tr>
              <td class="style23">Day:</td>
              <td><select name=dt >
<option value='01'>01</option>
<option value='02'>02</option>
<option value='03'>03</option>
<option value='04'>04</option>
<option value='05'>05</option>
<option value='06'>06</option>
<option value='07'>07</option>
<option value='08'>08</option>

<option value='09'>09</option>
<option value='10'>10</option>
<option value='11'>11</option>
<option value='12'>12</option>
<option value='13'>13</option>
<option value='14'>14</option>
<option value='15'>15</option>
<option value='16'>16</option>
<option value='17'>17</option>

<option value='18'>18</option>
<option value='19'>19</option>
<option value='20'>20</option>
<option value='21'>21</option>
<option value='22'>22</option>
<option value='23'>23</option>
<option value='24'>24</option>
<option value='25'>25</option>
<option value='26'>26</option>

<option value='27'>27</option>
<option value='28'>28</option>
<option value='29'>29</option>
<option value='30'>30</option>
<option value='31'>31</option>
</select></td>
            </tr>
            <tr>
              <td class="style23">Year:</td>
              <td><span class="style15">Year(yyyy)</span>
                <input name=year type=text value=2008 size=8 maxlength="4"></td>
            </tr>
          </table>
                        <p>
                          <input type="submit" name="Submit" value="Schedule Meeting!">
                        </p>
	</form>

 

Now, On the php that processes this... I want it to format it in unix timestamp according to the timezone they selected, hour, month, day, and year.

[jakebur01]

What if I want to customize my month, day, year, and hour into this?

 

Say the info from the form is:

 

$year='2008';

$day='23';

$month='8';

$hour='11';

$timezone='-4';

 

How could I turn this into a unix timestamp?

 

 

Do all your calculations against GMT (0) then.

$currentTime = gmdate(H);//Timestamp for GMT
$timeZone = '-8' //My Time offset - Pacific Cost
$eventTime = $currentTime + $timeZone
echo $eventTime;

 

If I ran this now it should output 10, as it's 10:35 here, you'll have to expand on it for the minutes, but it's the same process.

 

EDIT: I fixed some logic errors