php 数组长度 php5.5新数组函数array

php5.5新数组函数array  

　　PHP 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 : false;         $indexKeyIsNull         = (is_null($indexKey)) ? true : false;         $indexKeyIsNumber       = (is_numeric($indexKey)) ? true : false;         $result                 = array();         foreach((array)$input as $key=>$row){             if($columnKeyIsNumber){                 $tmp            = array_slice($row $columnKey );                 $tmp            = (is_array($tmp) && !empty($tmp)) ? current($tmp) : null;             }else{                 $tmp            = isset($row[$columnKey]) ? $row[$columnKey] : null;             }             if(!$indexKeyIsNull){                 if($indexKeyIsNumber){                     $key        = array_slice($row $indexKey );                     $key        = (is_array($key) && !empty($key)) ? current($key) : null;                     $key        = is_null($key) ? : $key;                 }else{                     $key        = isset($row[$indexKey]) ? $row[$indexKey] : ;                 }             }             $result[$key]       = $tmp;         }         return $result;     } } // 使用例子 $records = array(     array(         id =>         first_name => John         last_name => Doe     )     array(         id =>         first_name => Sally         last_name => Smith     )     array(         id =>         first_name => Jane         last_name => Jones     )     array(         id =>         first_name => Peter         last_name => Doe     ) ); $firstNames = array_column($records first_name ); print_r($firstNames); $records = array(     array( John Doe )     array( Sally Smith )     array( Jane Jones ) ); $lastNames = array_column($records ); print_r($lastNames); $mismatchedColumns = array(     array(         a => foo         b => bar         e => baz     )     array(         a => qux         c => quux         d => ce     )     array(         a => grault         b => garply         e => waldo     ) ); $foo = array_column($mismatchedColumns a b ); print_r($foo); 复制代码 代码如下: <?php // Array representing a possible record set returned from a database $records = array(     array(         id =>         first_name => John         last_name => Doe     )     array(         id =>         first_name => Sally         last_name => Smith     )     array(         id =>         first_name => Jane         last_name => Jones     )     array(         id =>         first_name => Peter         last_name => Doe     ) ); $first_names = array_column($records first_name ); print_r($first_names); ?> Array (     [ ] => John     [ ] => Sally     [ ] => Jane     [ ] => Peter )<?php // Using the $records array from Example # $last_names = array_column($records last_name id ); print_r($last_names); ?> Array (     [ ] => Doe     [ ] => Smith     [ ] => Jones     [ ] => Doe ) lishixinzhi/Article/program/PHP/201311/20974