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php组合生成一个特殊数组的问题

WBOY
WBOYOriginal
2016-06-06 20:50:371115browse

两个原数组

$arr['id'] = array(
[0] => '1',
[1] => false,
[2] => '3',
[3] => '4',
)

$arr['name'] = array(
[0] => 'zhang',
[1] => 'li',
[2] => 'du',
)

需要生成的数组

array(
[0]=>array('id'=>'1','name'=>'zhang'),
[1]=>array('id'=>false,'name'=>''),
[2]=>array('id'=>'3','name'=>'li'),
[3]=>array('id'=>'4','name'=>'du'),
)

回复内容:

两个原数组

$arr['id'] = array(
[0] => '1',
[1] => false,
[2] => '3',
[3] => '4',
)

$arr['name'] = array(
[0] => 'zhang',
[1] => 'li',
[2] => 'du',
)

需要生成的数组

array(
[0]=>array('id'=>'1','name'=>'zhang'),
[1]=>array('id'=>false,'name'=>''),
[2]=>array('id'=>'3','name'=>'li'),
[3]=>array('id'=>'4','name'=>'du'),
)

我大体理解了一下不知道对不对 ...

就是大数组里面的第一个小数组永远是最长的 ... 如果在这个数组里有 false 值则补全其他为空白 ...

写了段示例代码如下 ... 不止可以应用于你的情况 ... 源数组更复杂也可以处理 ...

<?php /* your array puts here ... primary key must be the first entry ... */
$arr = [
    'id'    =>  [ '1', false, '3', '4' ],
    'name'  =>  [ 'zhang', 'li', 'du' ]
];

/* get all key names ... */
$keys = array_keys( $arr );

/* use a different way to solve this ... */
var_export( array_reduce( $arr, 
    function( & $result, $current ) use ( & $keys ) {

    /* get current key name ... */
    $key = array_shift( $keys );

    /* first run ..? */
    if ( ! isset( $result ) )

        /* initialize a new array with primary key... */
        $result = array_map( function( $value ) use ( $key ) {

            /* just packing value as an array ... */
            return [ $key => $value ];

        /* value based on $current ... known as first entry of $arr ... */
        }, $current );

    /* when the array is built ... add new keys into it ... */
    else foreach ( $result as $num => & $value )

        /* leave blank when primary key is false or entry is empty ... */
        $value[$key] = ( false !== current( $value ) ) ?
            array_shift( $current ) ?: '' : '';

    /* send the new array back ... */
    return $result;

} ) );

原理就是根据原数组里面的第一个小数组建立主键 ... 然后根据主键把所有元素拼合在一起 ...

无所谓每个元素都叫什么名字 ... 也无所谓有多少元素 ... 除了主键数组之外其他小数组的键值完全不重要 ...

总之都按顺序拼在一起拼在一起变成另外一个大数组恩 ...

以及说 ... 如果小数组的长度超过主键数组长度的话 ... 超长的部分会被丢弃 ...

主键数组的长度超过小数组的话 ... 空缺的部分也会填入空白 ...

基本就是这样啦 ... 其实吧 ... 也可以简单的用 for 循环来完成 ... 效率还更高 ...

但用 array_reduce() 比较帅适应性也更强不是 ..?

$rev = array();
$ix = 0;
foreach($arr['id'] as $k=>$v){
   $rev[] = array(
      'id'=>$v,
      'name'=> $v ? $arr['name'][$ix++] : ''
   );
}
print_r($rev);

楼上给出来解释和非常漂亮的代码,下面我给个简单实现的。

$arr = array(
    'id'    =>  array('1', false, '3', '4' ),
    'name'  =>  array('zhang', 'li', 'du' )
);

foreach ($arr['id'] as $value) {
	if (intval($value) > 0) {
		$result[] = array(
			$value => array_shift($arr['name'])
		);
	} else {
		$result[] = array(
			$value => ''
		);
	}
}
var_dump($result);

不是用array_combine就好了吗……

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