与数字字符串键阵列Diddling [英] Diddling with arrays with numeric string keys

问题描述

要了解为什么我问这个，请参阅这并根据它的意见。请看下面的code：

To understand why I'm asking this, read this and the comments under it. Consider the following code:

$obj = new stdClass;
$obj->{10} = 'Thing';

$objArray = (array) $obj;
var_dump($objArray);

产地：

array(1) {
  ["10"]=>
  string(5) "Thing"
}

现在，我无法访问通过 $ objArray ['10'] ，因为PHP转换数字字符串键整数键。该手册明确规定整数属性不可访问在铸造一个数组的对象。还是他们？

Now, I can't access that via $objArray['10'] because PHP converts numeric strings keys to integer keys. The manual explicitly states "integer properties are unaccessible" upon casting an array to an object. Or are they?

要证明文档错了，我创建了一个类：

To prove the docs wrong, I created a class:

class strKey implements ArrayAccess
{
    private $arr;
    public function __construct(&$array)
    {
        $this->arr = &$array;
    }

    public function offsetExists($offset)
    {
        foreach ($this->arr as $key => $value)
        {
            if ($key == $offset)
            {
                return true;
            }
        }
        return false;
    }

    public function offsetGet($offset)
    {
        foreach ($this->arr as $key => $value)
        {
            if ($key == $offset)
            {
                return $value;
            }
        }
        return null;
    }

    public function offsetSet($offset, $value)
    {
        foreach($this->arr as $key => &$thevalue)
        {
            if ($key == $offset)
            {
                $thevalue = $value;
                return;
            }
        }

        // if $offset is *not* present...
        if ($offset === null)
        {
            $this->arr[] = $value;
        }
        else
        {
            // this won't work with string keys
            $this->arr[$offset] = $value;
        }
    }

    // can't implement this
    public function offsetUnset($offset)
    {
        foreach ($this->arr as $key => &$value)
        {
            if ($key == $offset)
            {
                //$value = null;
            }
        }
    }
}

现在，我能做的（演示）：

$b = new strKey($objArray);

echo $b['10']; // Thing
$b['10'] = 'Something else';

// because the classes works with a reference to the original array,
// this will give us a modified array:
var_dump($objArray); 

拼图的最后一块的，我怎么取消设置一个元素，其关键是一个数字字符串？我试着用 ArrayIterator ，键（），的next（）等，但它不会工作。我不能找到一种方法取消设置的。

The final piece of the puzzle is, how do I unset an element whose key is a numeric string? I tried using ArrayIterator, key(), next(), etc. but it won't work. I can't find a way unset those.

任何解决方案应与原阵列工作，而不是创建一个副本，取代原来的。

Any solution should work with the original array, not create a copy and replace the original.

推荐答案

您可以尝试使用删除array_splice（），如果你知道它的偏移量（的foreach（...）{$抵消++; ...} ），但存储这样的一个数组中的数据，实在不是一个好主意。您应该将这些对象转换为数组用foreach：

You can try to remove it with array_splice(), if you know its offset ( foreach (...) { $offset++; ... } ), but storing data in an arrays like this, is really not a good idea. You should convert these objects to array with foreach:

foreach ( $obj as $key => $value )
    $array[$key] = $value;

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