Need help sorting an array

[jimweinberg]

I'm writing a routine to build an array of filenames from a directory. Here's the code:

<?php
//call line: <script type="text/javascript" src="a/build_array.php?folder=b&array=c&usefilenames=d"></script>
// where a=relative location of the php script file
//       b=relative location of graphics folder
//       c=name of array to be built
//       d=use file names as captions:yes|no

Header("content-type: application/x-javascript");
function returnimages($arrayname) {
$dirname="../" . $_GET["folder"] . "/";
$pathname="" . $_GET["folder"] . "/";
$pattern="\.(jpg|jpeg|png|gif|bmp)$";
$curimage=0;
$str=',""';
if($handle = opendir($dirname)) {
while(false !== ($file = readdir($handle))){
if(eregi($pattern, $file)){
if($_GET["usefilenames"]=='yes')
$str = ', "' . preg_replace('/\.[^\.]*$/', '', $file) . '"';
echo $arrayname . '[' . $curimage .']=["' . $pathname . $file . '", "", ""' . $str . '];' . "\n";
$curimage++;
}
}

closedir($handle);
}
}

$arrayname=$_GET["array"];
echo 'var ' . $arrayname . '=new Array();' . "\n";
returnimages($arrayname);
?> 

The problem is that when I display the files using the array, they aren't in alphabetical order. I've tried adding a sort function [i.e. sort($arrayname);] but it doesn't work.

Can anyone tell me how to do the sort?

I should note that the file names are both alphabetic (i.e. Dscf0050.jpg) and numeric (i.e. 100-01234.jpg).

Thanks for your help.

[bradgrafelman]

Well the first problem I see about your array sorting solution is... you don't have an array to begin with. It's hard for PHP to sort an array that doesn't exist. 😉

I'd say you should split up the PHP code into two parts; one that builds a PHP array of values, and one that converts that PHP array into JavaScript code. You could also get rid of the second piece and just use [man]JSON[/man] to send the PHP array to the browser (which would then decode the JSON string back into an array in Javascript).

Once you've done the first part, [man]sort/man (or [man]natsort/man/[man]natcasesort/man, depending upon how you precisely define "alphabetical order") should work.

EDIT: By the way, the first part could be greatly simplified by ditching the old opendir/readdir method (as well as the deprecated eregi() function call) and instead using [man]glob/man.

[jimweinberg]

bradgrafelman. I don't understand your comment. I've used this routine, passing the array name to a slideshow routine, several times and it has always worked. I don't see how it could have if, as you say, there is no array. As to the older code, I've used this routine for a number of years and it's always worked. I believe that if it isn't broke, why fix it.

Perhaps someone else could provide me with a different view on how to solve my problem.

[bradgrafelman]

In your function below (reformatted so that it's at least moderately easy for a human to read):

function returnimages($arrayname) {
    $dirname="../" . $_GET["folder"] . "/";
    $pathname="" . $_GET["folder"] . "/";
    $pattern="\.(jpg|jpeg|png|gif|bmp)$";
    $curimage=0;
    $str=',""';

if($handle = opendir($dirname)) {
    while(false !== ($file = readdir($handle))) {
        if(eregi($pattern, $file)) {
            if($_GET["usefilenames"]=='yes')
                $str = ', "' . preg_replace('/\.[^\.]*$/', '', $file) . '"';

            echo $arrayname . '[' . $curimage .']=["' . $pathname . $file . '", "", ""' . $str . '];' . "\n";
            $curimage++;
        }
    }

    closedir($handle);
}
}

$arrayname is a string, not an array. You aren't creating a PHP array anywhere - you're just outputting text that eventually gets parsed by your browser and becomes an array in Javascript. That's why I emphasized building the array in PHP - something you aren't doing above.

[dalecosp]

As usual, BradG is correct ... there is no PHP array in the code you posted. The PHP does appear to produce Javascript that would create a Javascript "array" object (and possibly populate is via JSON ... I've not analyzed it that completely).

Perhaps someone else could provide me with a different view on how to solve my problem.

The PHP would need to be re-engineered. As Brad says, you could try something like glob() ... I typically use backtick operators and ls(1):

$filelist = `ls $somedirectory`;

That being said, a fairly easy way to get a PHP array from this call would be:

//this is UNIX specific (the newline character and the need to pop off a blank line.  YMMV on other systems).
$filelist = `ls $somedirectory`;
$files = array_pop(explode("\n",$filelist));

[dalecosp]

Aced by Brad ... apparently I had lunch before I actually posted the form....

[Derokorian]

You could of course sort it in javascript using Array.prototype.sort()

[bradgrafelman]

Derokorian;11040053 wrote:

You could of course sort it in javascript using Array.prototype.sort()

True... and that would offload the (albeit minor) CPU load from the server to the user's device. Win-win! 🙂

[johanafm]

But PHP-sorted or not - do [man]json_encode[/man] the array.

[jimweinberg]

Brad.

Thanks for the explanation. I don't do a lot of PHP coding and this looked like it would work. I think the reason it does is that the "array" name is passed to a javascript routine that does the display.

Dale & Derokorian.

Thank you for your suggestions. I will try them both.

Again, thanks to all for your help.