php5.5新数组函数array

php5.5发布了，其中增加了一个新的数组函数array_column，感觉不错的！但是低版本php要使用，得自己实现：
参考地址：

复制代码 代码如下:

if(!function_exists(‘array_column’)){

function array_column($input, $columnkey, $indexkey=null){

$columnkeyisnumber = (is_numeric($columnkey)) ? true : fal;

$indexkeyisnull = (is_null($indexkey)) ? true : fal;

$indexkeyisnumber = (is_numeric($indexkey)) ? true : fal;

$result = array();

foreach((array)$input as $key=>$row){

if($columnkeyisnumber){

$tmp = array_slice($row, $columnkey, 1);

$tmp = (is_array($tmp) && !empty($tmp)) ? current($tmp) : null;

}el{

$tmp = ist($row[$columnkey]) ? $row[$columnkey] : null;

}

if(!$indexkeyisnull){

if($indexkeyisnumber){

$key = array_slice($row, $indexkey, 1);

$key = (is_array($key) && !empty($key)) ? current($key) : null;

$key = is_null($key) ? 0 : $key;

}el{

$key = ist($row[$indexkey]) ? $row[$indexkey] : 0;

}

}

$result[$key] = $tmp;

}

return $result;

}

}

// 使用例子

$records = array(

array(

‘id圣诞主题’ => 2135,

‘first_name’ => ‘john’,

‘last_name’ =>上联贴左边还是右边; ‘doe’

),

array(

‘id’ => 3245,

‘first_name’ => ‘sally’,

‘last_name’ => ‘smith’

),

array(

‘id’ => 5342,

‘first_name’ => ‘jane’,

‘last_name’ => ‘jones’

),

array(

‘id’ => 5623,

‘first_name’ => ‘peter’,

‘last_name’ => ‘doe’

)

);

$firstnames = array_column($records, ‘first_name’);

print_r($firstnames);

/*

array

(

[0] => john

[1] => sally

[2] => jane

[3] => peter

)

*/

$records = array(

array(1, ‘john’, ‘doe’),

array(2, ‘sally’, ‘smith’),

array(3, ‘jane’, ‘jones’)

);

$lastnames = array_column($records, 2);

print_r($lastnames);

/*

array

(

[0] => doe

[1] => smith

[2] => jones

)

*/

$mismatchedcolumns = array(

array(

‘a’ => ‘foo’,

‘b’ => ‘bar’,

‘e’ => ‘baz’

),

array(

‘a’ => ‘qux’,

‘c’ => ‘quux’,

‘d’ => ‘corge’

),

array(酝酿怎么读

‘a’ => ‘grault’,

‘b’ => ‘garply’,

‘e’ => ‘waldo’

),

);

$foo = array_column($mismatchedcolumns, ‘a’, ‘b’);

print_r($foo);

/*

array

(

[bar] => foo

[0] => qux

[garply] => grault

)

*/

array_column 用于获取二维数组中的元素(php 5 >= 5.5.0)

复制代码 代码如下:

<?php

// array reprenting a possible record t returned from a databa

$records = array(

array(

‘id’ => 2135,

‘first_name’ => ‘john’,

‘last_name’ => ‘doe’,

),

array(

‘id’ => 3245,

‘first_name’ => ‘sally’,

‘last_name’ =>无私的反义词是什么; ‘smith&excel记账凭证模板#8217;,

),

array(

‘id’ => 5342,

‘first_name’ => ‘jane’,

‘last_name’ => ‘jones’,

),

array(

‘id’ => 5623,

‘first_name’ => ‘peter’,

‘last_name’ => ‘doe’,

)

);

$first_names = array_column($records, ‘first_name’);

print_r($first_names);

?>

array

(

[0] => john

[1] => sally

[2] => jane

[3] => peter

)<?php

// using the $records array from example #1

$last_names = array_column($records, ‘last_name’, ‘id’);

print_r($last_names);

?>

array

(

[2135] => doe

[3245] => smith

[5342] => jones

[5623] => doe

)