【PHP 每日函数】第 03 周期

﹏ヽ暗。殇╰゛Y 2022-03-06 02:44 115阅读 0赞

## 2019-02-27 ##

### array\_keys() ###

`array_keys ( array $array [, mixed $search_value = null [, bool $strict = false ]] ) : array`  
说明：获取数组中部分的或者所有的键名

$arr = [
        'name' => 'ZhangSan',
        'age' => 18,
        'gender' => 'man',
    ];
    
    print_r(array_keys($arr));
    
    // output
    Array
    (
        [0] => name
        [1] => age
        [2] => gender
    )

### array\_map() ###

`array_map ( callable $callback , array $array1 [, array $... ] ) : array`  
说明：为数组的每个元素应用回调函数

$arr = [1, 2, 6];
    
    print_r(array_map(function($value){
        return $value + 1;
    }, $arr))
    
    // output
    Array
    (
        [0] => 2
        [1] => 3
        [2] => 7
    )

### array\_merge() ###

`array_merge ( array $array1 [, array $... ] ) : array`  
说明：合并一个或者多个数组

$arr = [1, 2, 6];
    
    $arr2 = [2, 6, 7];
    
    print_r(array_merge($arr, $arr2));
    
    // output
    Array
    (
        [0] => 1
        [1] => 2
        [2] => 6
        [3] => 2
        [4] => 6
        [5] => 7
    )

### array\_multisort() ###

`array_multisort ( array &$array1 [, mixed $array1_sort_order = SORT_ASC [, mixed $array1_sort_flags = SORT_REGULAR [, mixed $... ]]] ) : bool`  
说明：对多个数组或者多维数组进行排序（具体可查看官网）

$data[] = array('volume' => 67, 'edition' => 2);
    $data[] = array('volume' => 86, 'edition' => 1);
    $data[] = array('volume' => 85, 'edition' => 6);
    $data[] = array('volume' => 98, 'edition' => 2);
    $data[] = array('volume' => 86, 'edition' => 6);
    $data[] = array('volume' => 67, 'edition' => 7);
    
    foreach ($data as $key => $value) {
        $volume[$key] = $value['volume'];
        $edition[$key] = $value['edition'];
    }
    
    array_multisort($volume, SORT_DESC, $edition, SORT_ASC, $data);
    
    print_r($data);
    
    // output
    Array
    (
        [0] => Array
            (
                [volume] => 98
                [edition] => 2
            )
    
        [1] => Array
            (
                [volume] => 86
                [edition] => 1
            )
    
        [2] => Array
            (
                [volume] => 86
                [edition] => 6
            )
    
        [3] => Array
            (
                [volume] => 85
                [edition] => 6
            )
    
        [4] => Array
            (
                [volume] => 67
                [edition] => 2
            )
    
        [5] => Array
            (
                [volume] => 67
                [edition] => 7
            )
    
    )

### array\_pop() ###

`array_pop ( array &$array ) : mixed`  
说明：弹出数组中最后一个单元

$arr = [1, 2, 6];
    array_pop($arr);
    print_r($arr);
    
    // output
    Array
    (
        [0] => 1
        [1] => 2
    )

### array\_product() ###

`array_product ( array $array ) : number`  
说明：计算数组中所有值的乘积

$arr = [1, 2, 6];
    print_r(array_product($arr));
    
    // output
    12

> 之前因为一些事，就没有每天都更，以后会坚持保持每天都更