跪求php 多维数组操作的问题，哪位好心人帮帮忙

[number123456]

数组

$a = array(
        "a"=>array(
                "ab"=>array(
                         "ab1" => "d",
                         "ab2" => "dd",
                      ),
                "ac"=>array(
                         "ac1" => "d",
                         "ac2" => "dd",
                      )
             ),
       "b" => array(
                "bb"=>array(
                         "bb1" => "d",
                         "bb2" => "dd",
                      ),
                "bc"=>array(
                         "bc1" => "d",
                         "bc2" => "dd",
                      )
             )

     );

我想根据数组
$d = array("a","ac","ac1");
来改变
$a["a"]["ac"]["ac1"] 的值，原来是"d"，我要改成"c"
请问要怎么来实现啊。

[number123456]

再重复一次，$d是不固定的，如果就只是现在这么固定的值的话很容易了，但是我要求的是一个方法
function setArray( $a,$d )
{
用什么方法能通过$d的数组来改变$a相应的值
}

[xuzuning]

$a = array(
        "a"=>array(
                "ab"=>array(
                         "ab1" => "d",
                         "ab2" => "dd",
                      ),
                "ac"=>array(
                         "ac1" => "d",
                         "ac2" => "dd",
                      )
             ),
       "b" => array(
                "bb"=>array(
                         "bb1" => "d",
                         "bb2" => "dd",
                      ),
                "bc"=>array(
                         "bc1" => "d",
                         "bc2" => "dd",
                      )
             )

     );

$d = array("a","ac","ac1");
$c = 'abcd';
eval('$a[' . join('][', $d) . '] = $c;');

print_r($a);

Array
(
[a] => Array
(
[ab] => Array
(
[ab1] => d
[ab2] => dd
)

[ac] => Array
(
[ac1] => abcd //这里被改变了
[ac2] => dd
)

)

[b] => Array
(
[bb] => Array
(
[bb1] => d
[bb2] => dd
)

[bc] => Array
(
[bc1] => d
[bc2] => dd
)

)

)

[number123456]

谢谢楼上的，你的意思是我想要的，
请问，用eval这样的操作会不会存在安全隐患？

[number123456]

对不起，我刚测试了，出现错误
Notice: Use of undefined constant a - assumed 'a' in E:\wamp\www\2.0\index.php(38) : eval()'d code on line 1

[max_soft]

$before_k = '';
$changed = 0;
foreach($d as $k) {
	global $before_k;
	if(!empty($a[$k]) && is_array($a[$k])) {
		continue;
	} else {
		$a[$before_k] = 'c';//不知道你这个C是怎么来的
		$changed = 1;
	}
	$before_k = $k
}
if(!$changed && $a[$before_k]) {
	$a[$curent_k] = 'c';
}

[max_soft]

$before_k = '';
$changed = 0;
foreach($d as $k) {
	global $before_k;
	if(!empty($a[$k]) && is_array($a[$k])) {
		continue;
	} else {
		$a[$before_k] = 'c';//不知道你这个C是怎么来的
		$changed = 1;
		break;
	}
	$before_k = $k
}
if(!$changed && $a[$before_k]) {
	$a[$curent_k] = 'c';
}

应该有个break

[max_soft]

我错了，再想想。。。

[amani11]

[Quote=引用 10 楼 number123456 的回复:]

对不起，我刚测试了，出现错误
Notice: Use of undefined constant a - assumed 'a' in E:\wamp\www\2.0\index.php(38) : eval()'d code on line 1
[/Quote]

改成eval('$a["' . join('"]["', $d) . '"] = $c;');

[number123456]

请问用eval会不会出现啥漏洞啊？有什么方法可以防一下吗？

[zhang6464]

感觉不该出错啊。。
[Quote=引用 10 楼 number123456 的回复:]
对不起，我刚测试了，出现错误
Notice: Use of undefined constant a - assumed 'a' in E:\wamp\www\2.0\index.php(38) : eval()'d code on line 1
[/Quote]

[number123456]

我换别的方法去做了，谢谢大家

[CunningBoy]

$a[$d[0]][$d[1]][$d[2]] = "c";

[amani11]

$d = array("a","ac","ac1");
if($a[$d[0]][$d[1]][$d[2]] == 'd')
{
  $a[$d[0]][$d[1]][$d[2]] = 'c';
}

[number123456]

楼不起，我没有说清楚
$d = array("a","ac","ac1");
这是个不定数量的组组，有可能是
$d = array("a");
或
$d = array("a","ac");
而且还有
$d = array("a","ad");这种可能，
就是说在$a["a"]中没有ad这一索引，那就默认把$a["a"]改掉

[xingworld]

if ( isset( $a[ $d[0] ][ $d[1] ][ $d[2] ] ) )
{
    $a[ $d[0] ][ $d[1] ][ $d[2] ] = 'c';
}

[number123456]

对不起，楼上的，我说过，$d变量是不因定的，也就是说，有多少个key是未知的，只能知道他的格式是一维数组。

[kyzy_yy_pm]

$d = array("a","ac","ac1");
来改变
$a["a"]["ac"]["ac1"] 的值，原来是"d"，我要改成"c"

$a[$d[0]][$d[1]][$d[2]] = 'c';