$a = ["a","b","c","a","b"];$b = ["a","c"];array_diff($a,$b);//output will be [b,b]但這不是一個(gè)適當(dāng)?shù)膮^(qū)別，它也可以是//output [b,a,b]  <- this is what I am trying to achieve我嘗試了 foreach 循環(huán)和 for 循環(huán)，但未能得到它...我試過(guò)的 Foreach 例子$a = ["a","b","c","a","b"];$b = ["a","c"];echo array_diff_custom($a,$b),"<br>";function array_diff_custom($a,$b){$result =0;    foreach($a as $key=>$val){        foreach($b as $key2=>$val2){                  if($val == $val2){                     unset($a[$key]);                   }                 }    }$result = count($a);return $result;}echo array_diff_custom($b,$a);for 循環(huán)示例，我試過(guò)了$a = ["a","b","c","a","b"];$b = ["a","c"];echo array_diff_custom($a,$b),"<br>";function array_diff_custom($a,$b){$result =0;    for($i=0;$i<count($a);$i++){        for($j=0;$j<count($b);$j++){                 //echo $a[$i]."-".$b[$j]."<br>";                  if($a[$i] == $b[$j]){                     unset($a[$i]);                   }                 }    }$result = count($a);return $result;}echo array_diff_custom($b,$a);我使用count($resut)的功能，例如我創(chuàng)建，但你可以只是簡(jiǎn)單的return $a和可print_R(array_Diff_custom) 檢查輸出...