php返回數組中指定的一列（php5.5.0默認函數array_column()在php
Mar 15, 2017 pm 01:23 PM
array_column() 返回數組中指定鍵名的列 (PHP 5 =5.5.0) array_column—返回數組中指定的一列
?如果php版本小于5.5.0怎么辦呢？我們自定義一個 以下代碼摘自onethink OneThink ThinkPHP
array_column() 返回數組中指定鍵名的列
(PHP 5 >= 5.5.0)
array_column — 返回數組中指定的一列
如果php版本小于5.5.0怎么辦呢？我們自定義一個
以下代碼摘自onethink OneThink ThinkPHP
/**
* 返回數組中指定的一列
* http://www.onethink.cn
* /Application/Common/Common/function.php
*
* array_column — PHP 5 >= 5.5.0 默認函數
* PHP 5 < 5.5.0 則使用自定義函數
*
* @access public
* @param array $input 需要取出數組列的多維數組（或結果集）
* @param string $columnKey 需要返回值的列，它可以是索引數組的列索引，或者是關聯(lián)數組的列的鍵。也可以是NULL，此時將返回整個數組（配合indexKey參數來重置數組鍵的時候，非常管用）
* @param string $indexKey 作為返回數組的索引/鍵的列，它可以是該列的整數索引，或者字符串鍵值。
* @return array
*/
if (! function_exists('array_column'))
{
function array_column(array $input, $columnKey, $indexKey = null)
{
$result = array();
if (null === $indexKey)
{
if (null === $columnKey)
{
$result = array_values($input);
}
else
{
foreach ($input as $row)
{
$result[] = $row[$columnKey];
}
}
}
else
{
if (null === $columnKey)
{
foreach ($input as $row)
{
$result[$row[$indexKey]] = $row;
}
}
else
{
foreach ($input as $row)
{
$result[$row[$indexKey]] = $row[$columnKey];
}
}
}
return $result;
}
}
<?php
// Array representing a possible record set returned from a database
$records = array(
array(
'id' => 2135,
'first_name' => 'John',
'last_name' => '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',
)
);
$first_names = array_column($records, 'first_name');
print_r($first_names);
?>
Array
(
[0] => John
[1] => Sally
[2] => Jane
[3] => Peter
)
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