Array_merge and array addition

Time:2019-6-19

array_merge()

Index array: Values will not be overwritten and will be re-indexed;
Associated Array: The last element overrides the other elements with the same key name.

 

Array+

To the left, the key is added;
Array
(
    [0] => A006
)
+
Array
(
    [0] => A004
    [1] => A006
)
=
Array
(
    [0] => A006
    [1] => A006
)