如何做到随机优先？ [复制]

这是我的代码，例如：

<?php
     $arr = array(
          array("url" => "http://google.com", "priority" => 2),
          array("url" => "http://facebook.com", "priority" => 2),
          array("url" => "http://youtube.com", "priority" => 2),
          array("url" => "http://stackoverflow.com", "priority" => 1),
          array("url" => "http://kickass.to", "priority" => 1),
          array("url" => "http://twitter.com", "priority" => 1),
          array("url" => "http://example.com", "priority" => 1),
     );
?>

我希望系统在每次刷新时随机显示其中一个网址。我希望它显示较高优先级的次数多于较低优先级的次数。我需要它用于横幅系统，并且具有较高优先级的支付更多，所以他们应该被更多地看到。

怎么做？

您可以根据项目的优先级将项目添加到数组中。如果某项的优先级为 2，则可以将其添加到数组中两次。然后你可以从数组中随机取出一个项目。

// CREATE A NEW ARRAY TO HOLD ALL OF THE BANNERS
$banner_array = array();     

// LOOP THROUGH EACH ITEM IN THE ARRAY CURRENTLY HOLDING THE BANNERS
foreach ($arr AS $banner) {

    // FOR EACH NUMBER IN THE PRIORITY, ADD THE ITEM TO OUR NEW ARRAY
    // google.com, facebook.com, youtube.com WILL BE ADDED IN TWICE
    for ($i = 0; $i < $banner['priority']; $i++) {
        $banner_array[] = $banner['url'];
    }
}

// COUNT THE TOTAL NUMBER OF ITEMS IN OUR ARRAY
// WE WILL PICK OUT A NUMBER BETWEEN ZERO AND THIS NUMBER (MINUS 1)
$item_count = count($banner_array) - 1;

// ONCE WE HAVE A RANDOM NUMBER, WE CAN ACCESS THAT ITEM OF THE ARRAY
print "RANDOM URL: ".$banner_array[get_random_item($item_count)];


// THIS FUNCTION PICKS A NUMBER BETWEEN ZERO AND THE NUMBER OF ITEMS IN OUR ARRAY
function get_random_item($item_count) {
    mt_srand(microtime() * 1000000);
    $random_number = rand(0, $item_count);
    return $random_number;
}