README

PHP 有用的数组方法

use duzun\ArrayClass as AC;

方法

::to_array

尝试将值转换为数组，或者当无法转换时返回值。

ArrayClass::to_array($object, $recursive=false)

$object 可以是 Generator、Traversable 或任何具有 ::getArrayCopy() 方法的对象。

示例

AC::to_array(1); // [1]
AC::to_array((function() { yield 1; })()); // [1]
AC::to_array(new \ArrayObject([1,2,3])); // [1,2,3]
AC::to_array($o = new class {}); // $o - don't know how to convert :(

::is_assoc

检查数组是否为关联数组（索引数组）。

ArrayClass::is_assoc($array, $strict = true): bool

示例

AC::is_assoc(['a','b','c']) === false;
AC::is_assoc([1 => 'a', 2 => 'b', 3 => 'c']) === true;
AC::is_assoc([1 => 'a', 2 => 'b', 3 => 'c'], false) === false;
AC::is_assoc(['x' => 'a', 2 => 'b', 3 => 'c'], false) === true;

::repeat

重复数组的值指定次数（比 array_fill() 更强大）。

ArrayClass::repeat(array $array, int $times): array

示例

// the most trivial case, same as array_fill(0, 3, 1);
AC::repeat([1], 3) === [1,1,1];
AC::repeat([1,2], 2) === [1,2,1,2];

// $times has to be positive
AC::repeat([1], 0) === [];
AC::repeat([1], -5) === [];

// doesn't preserve keys, ever
AC::repeat(['a' => 1, 'b' => 2, 'c' => 3], 3) === [1,2,3,1,2,3,1,2,3];
AC::repeat(['a' => 1, 'b' => 2, 'c' => 3], 1) === [1,2,3];

::cyclic_slice

类似于 array_slice()，但循环的，就像数组是一个环，我们可以从任何点以顺序方式取出任何数量的项。

ArrayClass::cyclic_slice(
    array $array,
    int $offset,
    int $length = NULL,
    bool $preserve_keys = false
): array

示例

AC::cyclic_slice(['a','b','c','d','e'], 1) === ['b','c','d','e','a']; // rotate by 1
AC::cyclic_slice(['a','b','c','d','e'], -1) === ['e','a','b','c','d']; // rotate by -1
AC::cyclic_slice(['a','b','c','d','e'], 1, 2) === ['b','c']; // slice 2 items
AC::cyclic_slice(['a','b','c','d','e'], 1, -2) === ['b','a']; // slice 2 items in reverse

// slice, while cycling, to fulfill the length
AC::cyclic_slice(['a','b','c','d'], 3, 9) === ['d','a','b','c','d','a','b','c','d'];
AC::cyclic_slice(['a','b','c','d'], -3, -9) === ['b','a','d','c','b','a','d','c','b'];

// preserve keys
AC::cyclic_slice(['a'=>1, 'b'=>2, 'c'=>3, 'd'=>4], 3, 3) === ['d'=>4, 'a'=>1, 'b'=>2];

::id

给定一个通过 ID 的项目列表，获取一个不在列表中存在的新 ID。

ArrayClass::id($array): int

示例

AC::id( NULL )                 === 1;
AC::id( [1] )                  === 1;
AC::id( [2=>1] )               === 3;
AC::id( [9=>0, 10=>1, 11=>2] ) === 12;

::group

根据字段列表对数组中的数组项进行分组。

ArrayClass::group($list, $fields, $as_list = false): array

示例

// Given an array of arrays:
$array = [
    [ 'a' => 1, 'b' => 3, 'c' => 7 ],
    [ 'a' => 1, 'b' => 3, 'c' => 8 ],
    [ 'a' => 1, 'b' => 5, 'c' => 9 ],
    [ 'a' => 2, 'b' => 3, 'c' => 10 ],
    [ 'a' => 2, 'b' => 5, 'c' => 11 ],
    [ 'a' => 2, 'b' => 5, 'c' => 11 ],
];

// group by values of field 'a', preserving the last appearance
AC::group($array, ['a']) == [
    1 => [ 'a' => 1, 'b' => 5, 'c' => 9 ],
    2 => [ 'a' => 2, 'b' => 5, 'c' => 11 ],
];

// group by values of field 'a', preserving all items by adding an extra level of depth.
AC::group($array, ['a'], true) == [
    1 => [
        [ 'a' => 1, 'b' => 3, 'c' => 7 ],
        [ 'a' => 1, 'b' => 3, 'c' => 8 ],
        [ 'a' => 1, 'b' => 5, 'c' => 9 ],
    ],
    2 => [
        [ 'a' => 2, 'b' => 3, 'c' => 10 ],
        [ 'a' => 2, 'b' => 5, 'c' => 11 ],
        [ 'a' => 2, 'b' => 5, 'c' => 11 ],
    ],
];

// group by two fields, preserving the last appearance
AC::group($array, ['a', 'b'], false) == [
    1 => [
        3 => [ 'a' => 1, 'b' => 3, 'c' => 8 ],
        5 => [ 'a' => 1, 'b' => 5, 'c' => 9 ],
    ],
    2 => [
        3 => [ 'a' => 2, 'b' => 3, 'c' => 10 ],
        5 => [ 'a' => 2, 'b' => 5, 'c' => 11 ],
    ],
];

请参阅代码文件中的其他方法 ArrayClass.php 和测试文件 ArrayClass.Test.php。

@TODO 测试并记录所有其他内容