PHP array_merge和 + 的区别

<?php

$a = ['php', 'j' => 'java', 'p' => 'python'];

$b = ['go', 'j' => 'javascript', 'r' => 'ruby'];

var_dump(array_merge($a, $b));

var_dump($a + $b);

array_merge:如果key为string，merge后后面数组会覆盖前面数组，如果key为int，键名会以连续方式重新索引。

array(5) {

  [0] =>

  string(3) "php"

  'j' =>

  string(10) "javascript"

  'p' =>

  string(6) "python"

  [1] =>

  string(2) "go"

  'r' =>

  string(4) "ruby"

}

+:如果key相等，相加后前面数组的值会覆盖后面数组的值

array(4) {

  [0] =>

  string(3) "php"

  'j' =>

  string(4) "java"

  'p' =>

  string(6) "python"

  'r' =>

  string(4) "ruby"

}