PHP pull random image from folder

问题:

I am wondering about a "better" way of pulling a random image from a folder.

Like say, to have php just select a random image from folder instead of searching and creating an array of it.

here is how I do it today

<?php
    $extensions = array('jpg','jpeg');
    $images_folder_path = ROOT.'/web/files/Header/';
    $images = array();
    srand((float) microtime() * 10000000);

    if ($handle = opendir($images_folder_path)) {
        while (false !== ($file = readdir($handle))) {
            if ($file != "." && $file != "..") {
                $ext = strtolower(substr(strrchr($file, "."), 1));
                if(in_array($ext, $extensions)){
                $images[] = $file;
                }
            }
        }
    closedir($handle);
    }
    if(!empty($images)){
        $header_image = $images[array_rand($images)];
    } else {
        $header_image = ''; 
    }
?>

回答1:

Try this:

<?php

$dir = "images/";
$images = scandir($dir);
$i = rand(2, sizeof($images)-1);
?>

<img src="images/<?php echo $images[$i]; ?>" alt="" />

回答2:

Below code validate image list by image extension.

<?php

function validImages($image)
{
    $extensions = array('jpg','jpeg','png','gif');
    if(in_array(array_pop(explode(".", $image)),   $extensions))
    {
    return $image;
    }
}

$images_folder_path = ROOT.'/web/files/Header/';
$relative_path = SITE_URL.'/web/files/Header/';

$images = array_filter(array_map("validImages", scandir($images_folder_path)));

$rand_keys = array_rand($images,1);

?>

<?php if(isset($images[$rand_keys])): ?>
    <img src="<?php echo $relative_path.$images[$rand_keys]; ?>" alt="" />
<?php endif; ?>

回答3:

function get_rand_img($dir)
{
    $arr = array();
    $list = scandir($dir);
    foreach ($list as $file) {
        if (!isset($img)) {
            $img = '';
        }
        if (is_file($dir . '/' . $file)) {
            $ext = end(explode('.', $file));
            if ($ext == 'gif' || $ext == 'jpeg' || $ext == 'jpg' || $ext == 'png' || $ext == 'GIF' || $ext == 'JPEG' || $ext == 'JPG' || $ext == 'PNG') {
                array_push($arr, $file);
                $img = $file;
            }
        }
    }
    if ($img != '') {
        $img = array_rand($arr);
        $img = $arr[$img];
    }
    $img = str_replace("'", "\'", $img);
    $img = str_replace(" ", "%20", $img);
    return $img;
}


echo get_rand_img('images');

replace 'images' with your folder.

回答4:

I searched the internet for hours on end to implement the code to what I wanted. I put together bits of various answers I found online. Here is the code:

<?php
    $folder = opendir("Images/Gallery Images/");
    $i = 1;
    while (false != ($file = readdir($folder))) {
        if ($file != "." && $file != "..") {
            $images[$i] = $file;
            $i++;
        }
    }
    //This is the important part... 
    for ($i = 1; $i <= 5; $i++) { //Starting at 1, count up to 5 images (change to suit)
        $random_img = rand(1, count($images) - 1);
        if (!empty($images[$random_img])) { //without this I was sometimes getting empty values
            echo '<img src="Images/Gallery Images/' . $images[$random_img] . '" alt="Photo ' . pathinfo($images[$random_img], PATHINFO_FILENAME) . '" />';
            echo '<script>console.log("' . $images[$random_img] . '")</script>'; //Just to help me debug
            unset($images[$random_img]); //unset each image in array so we don't have double images
        }
    }
?>

Using this method I was able to implement opendir with no errors (as glob() wasn't working for me), I was able to pull 5 images for a carousel gallery, and get rid of duplicate images and sort out the empty values. One downside to using my method, is that the image count varies between 3 and 5 images in the gallery, probably due to the empty values being removed. Which didn't bother me too much as it works as needed. If someone can make my method better, I welcome you to do so. Working example (the first carousel gallery at top of website): Eastfield Joinery