查找陣列匹配和刪除元素

Question

給定兩個數組：

$arr1 = (1, 0, 9); 
$arr2 = (8, 0, 2, 9, 4); 

我怎樣才能刪除$arr2，它由在$arr1的元素呢？
這將返回$arr3 = (8, 2, 4);

我已經試過這樣：

<?php 
foreach($arr1 as $item) 
{ 
     if(in_array($item, $arr2)) 
     { 
      # This is were I lose it, I've found a match then what? 
     } 
} 
?> 

Answer 1

array_diff是你要找的

什麼看一看here

$arr1 = array(1, 0, 9); 
$arr2 = array(8, 0, 2, 9, 4); 

echo print_r(array_diff($arr2,$arr1),true); 

>> Array ([0] => 8 [2] => 2 [4] => 4)