php - 简单的日期明智排序数组不起作用

Question

这是我的数组。(这个数组是例子)

Array(
        [0] => Array
            (
                [amt] => 50.00
                [transaction_date] => 2015-01-01
            )  
        [1] => Array
            (
                [amt] => 0.00
                [transaction_date] => 2015-02-01
            )

        [2] => Array
            (
                [amt] => 60.00
                [transaction_date] => 2015-01-01
            )
    )

我正在尝试根据日期对数组进行排序或分组。交易日期应该是一个意味着数组中没有重复的交易条目。我希望这个数组也应该按日期排序。意味着 2015-01-01 应该首先和 2015-02-01 在 2015-01-01 之后，如果日期可用，依此类推。

我想要如下的新数组

Array(
            [0] => Array
                (
                    [amt] => 110.00
                    [transaction_date] => 2015-01-01
                )

            [1] => Array
                (
                    [amt] => 0.00
                    [transaction_date] => 2015-02-01
                )            

        )

2015-01-01 此日期在数组中出现 2 次，每次重复时应添加 2 个不同的金额。数量应该是110

我试过了

$result = array();
foreach ($output as $key => $value) {
    $hash = $value['transaction_date'];
    if (isset($result[$hash])) {
        $result[$hash]['amt'] += $value['amt'];
        $result[$hash]['transaction_date'] = $value['transaction_date'];
    } else {
        $result[$hash]['amt'] = $value['amt'];
        $result[$hash]['transaction_date'] = $value['transaction_date'];
    }
}
print_r(array_values($result));

这是我实际的json编码结果

{"2015-07-18":{"amt":50,"transaction_date":"2015-07-18"},"2015-05-28":{"amt":"450.00","transaction_date":"2015-05-28"},"2015-06-02":{"amt":"200.00","transaction_date":"2015-06-02"},"2015-06-18":{"amt":"12610.00","transaction_date":"2015-06-18"},"2015-06-23":{"amt":"0.00","transaction_date":"2015-06-23"},"2015-06-24":{"amt":"603.00","transaction_date":"2015-06-24"},"2015-07-14":{"amt":"0.00","transaction_date":"2015-07-14"},"2015-07-16":{"amt":"0.00","transaction_date":"2015-07-16"},"2015-07-17":{"amt":"0.00","transaction_date":"2015-07-17"}} 

你可以在这个链接中查看这个数组 http://jsonviewer.stack.hu/

Answer 1

尝试简单地使用 usort 作为

$result = array();
foreach ($output as $key => $value) {
    $hash = $value['transaction_date'];
    if (isset($result[$hash])) {
        $result[$hash]['amt'] += $value['amt'];
        $result[$hash]['transaction_date'] = $value['transaction_date'];
    } else {
        $result[$hash]['amt'] = $value['amt'];
        $result[$hash]['transaction_date'] = $value['transaction_date'];
    }
}

uasort(array_values($result),function($a,$b){
     return $a['transaction_date'] - $b['transaction_date'];
});
print_r(array_values($result));

Demo