array_walk和array_map对每个数组值的trim操作

$tmp = [' AAA BBB CCC ', ' aaa bbb c ', ' ddd eee '];

function array_walk_func(&$v, $k) {

　　$v = trim($v);

array_walk($tmp, 'array_walk_func');

var_dump($tmp);

function array_map_func($v) {

　　return trim($v);

$ret = array_map('array_map_func', $tmp);

var_dump($ret);

输出结果：

array(3) {
  [0] =>
  string(14) "AAA BBB CCC"
  [1] =>
  string(11) "aaa bbb c"
  [2] =>
  string(13) "ddd eee"
}
array(3) {
  [0] =>
  string(14) "AAA BBB CCC"
  [1] =>
  string(11) "aaa bbb c"
  [2] =>
  string(13) "ddd eee"
}