根据数组的大小，我发现

$array = array_values( array_flip( array_flip( $array ) ) );

可以比array_unique快。

试试这个简短而甜蜜的代码-

$array = array (1,4,2,1,7,4,9,7,5,9);
$unique = array();

foreach($array as $v){
  isset($k[$v]) || ($k[$v]=1) && $unique[] = $v;
  }

var_dump($unique);

输出-

array(6) {
  [0]=>
  int(1)
  [1]=>
  int(4)
  [2]=>
  int(2)
  [3]=>
  int(7)
  [4]=>
  int(9)
  [5]=>
  int(5)
}

我们可以很容易地使用arar_unique ($array);删除重复的元素 但是这个方法的问题是元素的索引不是按顺序的，如果以后在其他地方使用会引起问题。

Use

$arr = array_unique($arr);
$arr = array_values($arr);
print_r($arr);

Or

$arr = array_flip($arr);
$arr = array_flip($arr);
$arr = array_values($arr);
print_r($arr);

第一次翻转，翻转键值对，从而将具有相似键(即最初的值)的元素组合在一起。

第二次翻转还原所有键值对。最后，array_value()设置每个值的key从0开始。

注意:不能用于具有预定义键值对的关联数组

$a = array(1, 2, 3, 4); 
$b = array(1, 6, 5, 2, 9); 
$c = array_merge($a, $b);
$unique = array_keys(array_flip($c));
print_r($unique);

这个例子只是一个替代。

    <?php
    $numbers = [1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,65776567567,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1,1,3,4,5,6,2,5,7,1];
    $unique_numbers = [];
    
    foreach($numbers as $number)
    {
      if(!in_array($number,$unique_numbers)){
          $unique_numbers[] = $number;
      }
    }
    print(json_encode($unique_numbers)); //// Array is now 1,3,4,5,6,2,7, ....

$array = array("a" => "moon", "star", "b" => "moon", "star", "sky");

// Deleting the duplicate items
$result = array_unique($array);
print_r($result);

参考:演示