PHP和UniApp实现数据的分组与统计的技巧

$data = [
    ['name' => '张三', 'age' => 18],
    ['name' => '李四', 'age' => 20],
    ['name' => '王五', 'age' => 18],
    ['name' => '赵六', 'age' => 20],
];

$groupedData = [];
foreach ($data as $item) {
    $groupedData[$item['age']][] = $item;
}

print_r($groupedData);

[
    18 => [
        ['name' => '张三', 'age' => 18],
        ['name' => '王五', 'age' => 18],
    ],
    20 => [
        ['name' => '李四', 'age' => 20],
        ['name' => '赵六', 'age' => 20],
    ],
]

$data = ['a', 'b', 'a', 'c', 'b', 'a'];

$counts = array_count_values($data);
arsort($counts);

print_r($counts);

[
    'a' => 3,
    'b' => 2,
    'c' => 1,
]

import { groupBy, countBy } from 'lodash';

const data = [
    { name: '张三', age: 18 },
    { name: '李四', age: 20 },
    { name: '王五', age: 18 },
    { name: '赵六', age: 20 },
];

const groupedData = groupBy(data, 'age');
console.log(groupedData);

{
    18: [
        { name: '张三', age: 18 },
        { name: '王五', age: 18 }
    ],
    20: [
        { name: '李四', age: 20 },
        { name: '赵六', age: 20 }
    ]
}

const data = ['a', 'b', 'a', 'c', 'b', 'a'];

const counts = countBy(data);
console.log(counts);

{
    'a': 3,
    'b': 2,
    'c': 1
}