php 對多維陣列的操作,該怎麼解決

php 對多維陣列的操作
我想將資料迴圈插入多維陣列，請問該怎麼做？
代碼如下：

$a=array("date"=>array
(
"msg1"=>"asdasd",
"msg2"=>"dasdsa")
);
/*----------如何將一個資料添加到數組中，使數組輸出如下---------------------*/
/*   Array ( [date] => Array ( [msg1] => asdasd [msg2] => dasdsa[msg3] => dasdsa[msg4] => dasdsa ) )   */

我用了array_push函數，可是結果不是我想要的。
代碼如下：

$a=array("date"=>array("msg1"=>"asdasd","msg2"=>"dasdsa"));
array_push($a['date'],array('msg3'=>'tel'));
print_r($a);

輸出結果是
Array ( [date] => Array ( [msg1] => asdasd [msg2] => dasdsa [0] => Array ( [msg3] => tel ) ) )
但我想要的是 Array ( [date] => Array ( [msg1] => asdasd [msg2] => dasdsa [msg3] => tel ) )
請問如何才能做到？求大神幫忙。
急需！！！
------解決方案--------------------

$a=array();
foreach($data as $k=>$v){
  $a['date']['msg'.$k]=$v;
}
print_r($a);

------解決方案--------------------

$a=array("date"=>array("msg1"=>"asdasd","msg2"=>"dasdsa"));
$a['date']['msg3'] = 'tel';
print_r($a);

Array
(
    [date] => Array
        (
            [msg1] => asdasd
            [msg2] => dasdsa
            [msg3] => tel
        )

)

------解決方案--------------------

$a=array("date"=>array("msg1"=>"asdasd","msg2"=>"dasdsa"));
$a['date']['msg3'] = 'tel';
print_r($a);

Array
(
    [date] => Array
        (
            [msg1] => asdasd
            [msg2] => dasdsa
            [msg3] => tel
        )
 
)

------解決方案--------------------

$a=array("date"=>array("msg1"=>"asdasd","msg2"=>"dasdsa"));
$a = array_merge_recursive($a, array('date' => array('msg3'=>'tel')));
print_r($a);

Array
(
    [date] => Array
        (
            [msg1] => asdasd
            [msg2] => dasdsa
            [msg3] => tel
        )

)

