php从数组中随机选择若干不重复元素的方法

<?php

/*

 * $array = the array to be filtered

 * $total = the maximum number of items to return

 * $unique = whether or not to remove duplicates before getting a random list

 */

function unique_array($array, $total, $unique = true){

    $newArray = array();

    if((bool)$unique){

        $array = array_unique($array);

    }

    shuffle($array);

    $length = count($array);

    for($i = 0; $i < $total; $i++){

        if($i < $length){

            $newArray[] = $array[$i];

        }

    }

    return $newArray;

}

$phrases = array('Hello Sailor','Acid Test','Bear Garden','Botch A Job','Dark Horse',

    'In The Red','Man Up','Pan Out','Quid Pro Quo','Rub It In','Turncoat',

    'Yes Man','All Wet','Bag Lady','Bean Feast','Big Wig', 'Big Wig','Bear Garden'

    ,'All Wet','Quid Pro Quo','Rub It In');

print_r(unique_array($phrases, 1));

// Returns 1 result

print_r(unique_array($phrases, 5));

// Returns 5 unique results

print_r(unique_array($phrases, 5, false));

// Returns 5 results, but may have duplicates if

// there are duplicates in original array

print_r(unique_array($phrases, 100));

// Returns 100 unique results    

print_r(unique_array($phrases, 100, false));

// Returns 100 results, but may have duplicates if

// there are duplicates in original array