有时候我们需要将两个数组合并，并且将某些键值再次合并成一个数组。
想了很多方法，都不理想，最后百度看了一个不错的方法，在这里分享给大家。
<?php
$a=array(
array("username"=>"piaoyudesi","email"=>"piaoyudesi@163.com","address"=>"shenzhen","item_id"=>"10058","item_title"=>"BPS8"),
array("username"=>"huakai","email"=>"huakai@163.com","address"=>"zhongshan","item_id"=>"10087","item_title"=>"BPS9"),
array("username"=>"huakai","email"=>"huakai@163.com","address"=>"zhongshan","item_id"=>"10047","item_title"=>"BPS10"),
array("username"=>"piaoyudesi","email"=>"piaoyudesi@163.com","address"=>"shenzhen","item_id"=>"10042","item_title"=>"BPS10"),
array("username"=>"jimowenxin","email"=>"jimowenxin@163.com","address"=>"zhuhai","item_id"=>"10031","item_title"=>"BPS18")
);
$u=array();
foreach($a as $k=>&$e){
$name=&$e['username'];
if(!isset($u[$name])){
$u[$name]=$e;
unset($u[$name]['item_id'],$u[$name]['item_title']);
}
$u[$name]['goods'][]=array('item_id'=>$e['item_id'],'item_title'=>$e['item_title']);
}
$a=array_values($u); unset($u);
print_r($a);
=========
Array
(
[0] => Array
(
[username] => piaoyudesi
[email] => piaoyudesi@163.com
[address] => shenzhen
[goods] => Array
(
[0] => Array
(
[item_id] => 10058
[item_title] => BPS8
)
[1] => Array
(
[item_id] => 10042
[item_title] => BPS10
)
)
)
[1] => Array
(
[username] => huakai
[email] => huakai@163.com
[address] => zhongshan
[goods] => Array
(
[0] => Array
(
[item_id] => 10087
[item_title] => BPS9
)
[1] => Array
(
[item_id] => 10047
[item_title] => BPS10
)
)
)
[2] => Array
(
[username] => jimowenxin
[email] => jimowenxin@163.com
[address] => zhuhai
[goods] => Array
(
[0] => Array
(
[item_id] => 10031
[item_title] => BPS18
)
)
)
)
