php将数组转换为多维数组答案

【问题标题】：php turning array into multi-dimensional arrayphp将数组转换为多维数组
【发布时间】：2011-12-09 17:17:54
【问题描述】：

我有一个（动态）数组，在本例中包含 4 组数据（每组 5 个字段），但它可能只有一组或最多 25 组。

Array ( [lightwattage1] => 50 [lightvoltage1] => 12 [lightquantity1] => 2 [lightusage1] => 4 [lightcomment1] => [lightwattage2] => 60 [lightvoltage2] => 24 [lightquantity2] => 4 [lightusage2] => 5 [lightcomment2] => [lightwattage3] => 30 [lightvoltage3] => 240 [lightquantity3] => 4 [lightusage3] => 2 [lightcomment3] => [lightwattage4] => 25 [lightvoltage4] => 12 [lightquantity4] => 2 [lightusage4] => 6 [lightcomment4] => )

我想把它变成类似的东西

Array ( Array ( [lightwattage1] => 50 [lightvoltage1] => 12 [lightquantity1] => 2 [lightusage1] => 4 [lightcomment1] => ),
        Array ( [lightwattage2] => 60 [lightvoltage2] => 24 [lightquantity2] => 4 [lightusage2] => 5 [lightcomment2] => ),
        Array ( [lightwattage3] => 30 [lightvoltage3] => 240 [lightquantity3] => 4 [lightusage3] => 2 [lightcomment3] => ), 
        Array ( [lightwattage4] => 25 [lightvoltage4] => 12 [lightquantity4] => 2 [lightusage4] => 6 [lightcomment4] => )
        )

原始数组是这样创建的：

$light = Array();

foreach( $_POST as $key => $val )
{
//field names that start with light to go in this array
    if (strpos($key, 'light') === 0) {
        $light[$key] = $val;
    }
}

字段名称数字是在提交表单之前已经用JS添加的，而不是通过php脚本添加的。非常感谢任何提示。

【问题讨论】：

遍历原始数组，当您看到已经设置了一个键时，您就会知道是时候开始将数据放入新的子数组中了。

标签： php arrays loops multidimensional-array

【解决方案1】：

这不是您问题的确切答案，但是...

您可以像这样在POST 变量中使用数组：

<input name="light[1][wattage]" />
<input name="light[1][voltage]" />
<input name="light[2][wattage]" />
<input name="light[2][voltage]" />

会给你：

$_POST['light'] == array(
    1 => array(
        'wattage' => '...',
        'voltage' => '...',
    ),
    2 => array(
        'wattage' => '...',
        'voltage' => '...',
    ),
)

【讨论】：

我喜欢这种方法，但我必须重写我的表单、它的 jQUery 和 JS 验证。下次我会用这个。欢呼

【解决方案2】：

试试这个：

$prefixes = array();
$postfixes = array();
foreach($original_array as $key=>$value)
{
        preg_match('/^([^\d]*)(\d+)$/',$key,$matches);
        if(count($matches)>1)
        {
                if(!in_array($matches[1], $prefixes)) $prefixes[] = $matches[1];
                if(!in_array($matches[2], $postfixes)) $postfixes[] = $matches[2];
        }
}   
$new_array = array();
foreach($postfixes as $postfix)
{
        $new_element = array();
        foreach($prefixes as $prefix)
        {
                if(isset($original_array[$prefix.$postfix])) $new_element[$prefix.$postfix] = $original_array[$prefix.$postfix];
        }
        $new_array[] = $new_element; 
}

给定一个等于描述的$original_array，将产生$new_array：

Array
(
    [0] => Array
        (
            [lightwattage1] => 50
            [lightvoltage1] => 12
            [lightquantity1] => 2
            [lightusage1] => 4
            [lightcomment1] => 
        )

    [1] => Array
        (
            [lightwattage2] => 60
            [lightvoltage2] => 24
            [lightquantity2] => 4
            [lightusage2] => 5
            [lightcomment2] => 
        )

    [2] => Array
        (
            [lightwattage3] => 30
            [lightvoltage3] => 240
            [lightquantity3] => 4
            [lightusage3] => 2
            [lightcomment3] => 
        )

    [3] => Array
        (
            [lightwattage4] => 25
            [lightvoltage4] => 12
            [lightquantity4] => 2
            [lightusage4] => 6
            [lightcomment4] => 
        )

)

我不确定你对元素或它们的顺序了解多少，所以这段代码基本上采用任何以数字结尾的元素集合，并将它们重新排列在具有相同结尾数字的组中。

【讨论】：

糟糕，如果只有一位数字，这很好用，但一旦超过 9（lightwattage10 等），脚本就会失败。
改变 preg_match 行成功了：preg_match('/^(.*)(\d+)$/',$key,$matches); 到 preg_match('/^([^0-9]*)(\d+)$/',$key,$matches);

【解决方案3】：

试试这个：

$outarr = array()
$subarr = array()
$i=0;
foreach($_POST as $key => $val)
{
    //only include keys starting with light:
    if (strpos("light", $key)==0)
    {
        //create a new subarray each time we find a key that starts with "lightwattage":
        if ($i>0 && strpos("lightwattage", $key)==0)
        {
            $outarr[] = $subarr;
        }
        $subarr[$key] = $val;
        $i++;
    }
}
$outarr[] = $subarr;

//$outarr contains what you want here

【讨论】：