More Efficient Way than Daisy-chained if statements...

[wintallo]

Hey,

 

I'm making a program that need a dropdown menu with timezones in it. So I wrote a function to output the menu, with an optional parameter of certain timezone to have automatically selected.

here's my code.

function output_timezone_menu($timezone = 0) {
echo "<select name=\"timezone\">";
if ( $timezone == -12 ) { echo "<option value=\"-12\">GMT - 12 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"-12\">GMT - 12 Hours</option>"; }
if ( $timezone == -11 ) { echo "<option value=\"-11\">GMT - 11 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"-11\">GMT - 11 Hours</option>"; }
if ( $timezone == -10 ) { echo "<option value=\"-10\">GMT - 10 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"-10\">GMT - 10 Hours</option>"; }
if ( $timezone == -9 ) { echo "<option value=\"-9\">GMT - 9 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"-9\">GMT - 9 Hours</option>"; }
if ( $timezone == -8 ) { echo "<option value=\"-8\">GMT - 8 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"-8\">GMT - 8 Hours</option>"; }
if ( $timezone == -7 ) { echo "<option value=\"-7\">GMT - 7 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"-7\">GMT - 7 Hours</option>"; }
if ( $timezone == -6 ) { echo "<option value=\"-6\">GMT - 6 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"-6\">GMT - 6 Hours</option>"; }
if ( $timezone == -5 ) { echo "<option value=\"-5\">GMT - 5 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"-5\">GMT - 5 Hours</option>"; }
if ( $timezone == -4 ) { echo "<option value=\"-4\">GMT - 4 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"-4\">GMT - 4 Hours</option>"; }
if ( $timezone == -3.5 ) { echo "<option value=\"-3.5\">GMT - 3.5 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"-3.5\">GMT - 3.5 Hours</option>"; }
if ( $timezone == -3 ) { echo "<option value=\"-3\">GMT - 3 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"-3\">GMT - 3 Hours</option>"; }
if ( $timezone == -2 ) { echo "<option value=\"-2\">GMT - 2 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"-2\">GMT - 2 Hours</option>"; }
if ( $timezone == -1 ) { echo "<option value=\"-1\">GMT - 1 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"-1\">GMT - 1 Hours</option>"; }
if ( $timezone == 0 ) { echo "<option value=\"0\">GMT</option>"; } else { echo "<option selected=\"selected\" value=\"0\">GMT</option>"; }
if ( $timezone == 1 ) { echo "<option value=\"1\">GMT + 1 Hour</option>"; } else { echo "<option selected=\"selected\" value=\"1\">GMT + 1 Hour</option>"; }
if ( $timezone == 2 ) { echo "<option value=\"2\">GMT + 2 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"2\">GMT + 2 Hours</option>"; }
if ( $timezone == 3 ) { echo "<option value=\"3\">GMT + 3 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"3\">GMT + 3 Hours</option>"; }
if ( $timezone == 3.5 ) { echo "<option value=\"3.5\">GMT + 3.5 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"3.5\">GMT + 3.5 Hours</option>"; }
if ( $timezone == 4 ) { echo "<option value=\"4\">GMT + 4 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"4\">GMT + 4 Hours</option>"; }
if ( $timezone == 4.5 ) { echo "<option value=\"4.5\">GMT + 4.5 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"4.5\">GMT + 4.5 Hours</option>"; }
if ( $timezone == 5 ) { echo "<option value=\"5\">GMT + 5 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"5\">GMT + 5 Hours</option>"; }
if ( $timezone == 5.5 ) { echo "<option value=\"5.5\">GMT + 5.5 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"5.5\">GMT + 5.5 Hours</option>"; }
if ( $timezone == 6 ) { echo "<option value=\"6\">GMT + 6 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"6\">GMT + 6 Hours</option>"; }
if ( $timezone == 6.5 ) { echo "<option value=\"6.5\">GMT + 6.5 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"6.5\">GMT + 6.5 Hours</option>"; }
if ( $timezone == 7 ) { echo "<option value=\"7\">GMT + 7 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"7\">GMT + 7 Hours</option>"; }
if ( $timezone == 8 ) { echo "<option value=\"8\">GMT + 8 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"8\">GMT + 8 Hours</option>"; }
if ( $timezone == 9 ) { echo "<option value=\"9\">GMT + 9 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"9\">GMT + 9 Hours</option>"; }
if ( $timezone == 9.5 ) { echo "<option value=\"9.5\">GMT + 9.5 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"9.5\">GMT + 9.5 Hours</option>"; }
if ( $timezone == 10 ) { echo "<option value=\"10\">GMT + 10 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"10\">GMT + 10 Hours</option>"; }
if ( $timezone == 11 ) { echo "<option value=\"11\">GMT + 11 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"11\">GMT + 11 Hours</option>"; }
if ( $timezone == 12 ) { echo "<option value=\"12\">GMT + 12 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"12\">GMT + 12 Hours</option>"; }
if ( $timezone == 13 ) { echo "<option value=\"13\">GMT + 13 Hours</option>"; } else { echo "<option selected=\"selected\" value=\"13\">GMT + 13 Hours</option>"; }
echo "</select>";
}

Is there a more elegant or faster way to do this? It seems like all of the if statements could really slow down the load time. What I'm asking is there some other condition structure I could use to speed up the process?

 

Thanks!

 

-wintallo

[toplay]

A switch statement can be used, but a better approach is simply to use an array to hold your timezone values. Then simply use "for" or "foreach" to walk through the array and display.

 

[kenrbnsn]

Put all the possible timezones in an array and loop through the array:

<?php
function output_timezone_menu($timezone = 0) {
   $tzones = array(-12,-11,-10,-9,-8,-7,-6,-5,-4,-3.5,-3,-2,-1,0,1,2,3,3.5,4,4.5,5,5.5,6,6.5,7,8,9,9.5,10,11,12,13);
   $tmp = array();
   $tmp[] = '<select name="timezone">';
   foreach ($tzones as $tz) {
       $sel = ($tz == $timezone)?' selected="selected"':'';
       $mp = ($tz < 0)?' - ':' + ';
       $gmt = ($tz != 0)?'GMT' . $mp . abs($tz) . ' Hours':'GMT';
       $tmp[] = '<option value="' . $tz . '"' . $sel . '>' . $gmt . '</option>';
   }
   $tmp[] = '</select>';
   echo implode("\n",$tmp) . "\n";
}

?>

 

Tested. Works.

 

Ken

[wintallo]

Thanks a lot guys!

 

<solved>

[haku]

Don't just type <solved>, click the 'solved' button. The whole point is for people to be able to see that the problem has been solved without coming into the thread.

[kenrbnsn]

The "Solved" button has been MIA since the forum was upgraded a few days ago.

 

Ken

[haku]

Crappy! My apologies to wintallo.