PHP 關聯索引鍵區分大小寫,索引鍵「a」與索引鍵「A」不同
<?php
$arr = ["A" => 666];
var_dump($arr["a"]);
var_dump($arr["A"]);
?>
產生
NULL
int(666)
同樣地,array_diff_assoc 會區分索引鍵的大小寫,索引鍵「A」不等於索引鍵「a」,且會被視為差異
<?php
$compareWhat = ["a" => 666, "b" => 666, "c" => 666, ];
$compareWith = ["A" => 666, "b" => 667, "c" => 666, ];
var_dump(array_diff_assoc($compareWhat, $compareWith));
?>
產生
array(2) {
["a"]=> int(666)
["b"]=> int(666)
}
如果陣列中的值順序不同,結果的順序也會不同,但本質上結果保持不變
<?php
$compareWhat = ["b" => 666, "a" => 666, "c" => 666, ];
$compareWith = ["A" => 666, "b" => 667, "c" => 666, ];
var_dump(array_diff_assoc($compareWhat, $compareWith));
?>
產生
array(2) {
["b"]=> int(666)
["a"]=> int(666)
}