php 数组在键不相同或者去重可以用数组加和

前面的数组覆盖后面数组键相同的值

$a = array("a" => "apple", "b" => "banana");

$b = array("a" => "apple", "b" => "banana", "c" => "cherry");

$c = $a + $b; //print array("a" => "apple", "b" => "banana", "c" => "cherry") 

或者

$a = array("a" => "apple", "b" => "banana");

$b = array("apple","banana","cherry");

$c = $a +$b;//print array("a" => "apple", "b" => "banana","apple","banana"，“cherry”)