1，array_intersect() 返回一个数组，该数组包含了所有在 array1 中也同时出现在所有其它参数数组中的值。注意键名保留不变。
$array1 = array("a" = "green", "red", "blue"); $array2 = array("b" ="green", "yellow", "red"); $result = array_intersect($array1, $array2); print_r($result); 结果：Array ( [a] = green [0] = red )
2，array_diff() 返回一个数组，该数组包括了所有在 array1 中但是不在任何其它参数数组中的值。注意键名保留不变。
$array1 = array("a" ="green", "red", "blue", "red"); $array2 = array("b" ="green", "yellow", "red"); $result = array_diff($array1, $array2); print_r($result); 结果：Array ([1] = blue)
3，array_merge — 合并一个或多个数组
$array1 = array("color" => "red", 2, 4); $array2 = array("a", "b", "color" => "green", "shape" => "trapezoid", 4); $result = array_merge($array1, $array2); print_r($result); 结果： Array ([color] => green [0] => 2 [1] => 4[2] => a [3] => b [shape] => trapezoid)
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testing