multiple random images from same array

[arumdevil]

Hi all...

 

I am new to the forum and new to PHP, so be gentle. I have been searching the web for this all day so forgive me if I have missed a post that answers my question.

 

I want to display 4 images (but with possibility of more in future) on a page which are randomly selected from a number of possible images. at the moment I have each possible image as a list in an array, and have found it simple enough to generate the 4 images randomly. The problem I am having is that I don't want the same image to appear more than once, and am having trouble doing this.

 

As I said, I am new to PHP so I have a lot to learn, but I have built a (fairly basic, admitedly) application in AppleScript on a mac, so I am familiar with many of the basic concepts behind programming, and I could do what I want in AppleScript, but am having trouble translating it to PHP, plus it's been a while since I did that anyway.

 

I'm sure there must be a simple answer, but I can't find it so any suggestions would be greatly appreciated.

 

Here is the script I have so far: (any tips to clean it up also welcome!)

<?php 
		$file_array = array
		(
			'93.jpg', 
			'96.jpg',
			'900.jpg',
			'962.jpg',
			'93.jpg',
			'93.jpg',
			'aerobadge.jpg',
			'aeroX1.jpg',
			'aeroX2.jpg',
			'aeroX3.jpg', 
		); 

		$total = count($file_array); 

		$random = (mt_rand()%$total); 
		$file1 = "$file_array[$random]";
		$file_array= array_values($file_array);

		$random = (mt_rand()%$total); 
		$file2 = "$file_array[$random]";
		$file_array= array_values($file_array);

		$random = (mt_rand()%$total); 
		$file3 = "$file_array[$random]";
		$file_array= array_values($file_array);

		$random = (mt_rand()%$total); 
		$file4 = "$file_array[$random]";

 

Now I tried to get what I want using if statements or repeat loops but one got very confusing and the other froze up the CPU and didn't really work anyway!

 

 

then I figured if I move through the images one by one, removing it from the array as it is used, that would solve it, but I couldn't get it to work....

 

 

any help appreciated,

 

arumdevil

 

[boo_lolly]

why don't you do something like this:

<?php
        $img_array = array('img1.jpg', 'img2.jpg', 'img3.jpg', 'img4.jpg', 'img5.jpg', 'img6.jpg', 'img7.jpg');
        shuffle($img_array);

        for($i = 0; $i < 4; $i++){
                echo $img_array[$i] ."<br />\n";
        }

        if(you want to display more){
                for($j = $i; $j < $displayNum; $j++){
                        echo $img_array[$j] ."<br />\n";
                }
        }
?>

[kenrbnsn]

Another way to do this is something like this:

<?php 
$file_array = array
(
	'93.jpg', 
	'96.jpg',
	'900.jpg',
	'962.jpg',
	'93.jpg',
	'93.jpg',
	'aerobadge.jpg',
	'aeroX1.jpg',
	'aeroX2.jpg',
	'aeroX3.jpg', 
); 
$rand_array = array();
$tst = $file_array[array_rand($file_array)];
for ($i=0;$i<4;$i++) {
	while (in_array($tst,$rand_array))
		$tst = $file_array[array_rand($file_array)];
	$rand_array[] = $tst;
}
echo '<pre>' . print_r($rand_array,true) . '</pre>'; // debug statement to see what's in the array
?>

 

Ken

[arumdevil]

thanks guys, both look like more efficient ways around the problem. As it turns out I have managed to get it working in the meantime, though not as efficiently as either of your suggestions. There were two problems with my original script, 1 being that the array had doubled up values in it which meant for a while while it was in fact working I thought it wasn't  very emarrasing...

 

anyway, I will play around with both of your suggestions to understand why and how they work.

 

thanks again.

 

humbly, arumdevil

[arumdevil]

awesome, thanks guys, I went for Ken's example in the end as I could make sense of it more easily and got it to show more images....but thank you both.

 

now to make it perfect, how can I get it to set the array to every image inside a particular folder? any thoughts on that?

 

thanks

 

arumdevil

[boo_lolly]

what do you mean set the array to particular folders??

[arumdevil]

sorry I wasn't clear. In the example above I have explicitly set each item (key??) of the array in the script. what I would like to do instead, is have the script dynamically set each item of the array to each image file inside a particular server on the folder, the purpose being that the user can then change the available images by simply adding them to and deleting them from the folder - with no need to edit the code...

 

hope that makes sense, sorry I've not learnt the proper terminology yet