如何在 php foreach 循环中从 json obj 获取值

Posted 2023-02-15

【中文标题】如何在 php foreach 循环中从 json obj 获取值

【英文标题】：how to get values from json obj in php foreach loop

【发布时间】：2022-01-13 15:34:02

【问题描述】：

我有几个 json 文件，每个 json 文件如下所示：

    "id": "id_1638974137049",
    "weeknr": 48,
    "dayhours": 5,
    "tvt": 1.25

另一个文件：

    "id": "id_1638974137050",
    "weeknr": 48,
    "dayhours": 6,
    "tvt": 1.50

还有一个：

    "id": "id_1638974137023",
    "weeknr": 48,
    "dayhours": 7,
    "tvt": 1.75

现在我想制作一个表格作为输出，其中包含该周的 weeknr、dayhours 和 tvthours。这是我到目前为止所拥有的：

$files = glob('data/*.json'); // all json files in array
foreach($files as $file) 
        $objs[] = json_decode(file_get_contents($file), true); // decode to php assoc array             
    
foreach($objs as $key => $val) 
    $weeknr = $val['weeknr']; // weeknr

    $array_dayhours[$weeknr] += $val['dayhours']; // sum of all the dayhours from that week
    $array_tvthours[$weeknr] += $val['tvt']; // sum of all the tvt hours from that week
    // i dont know how to handle this further to create a new array which contains per week the dayhours and tvt hours 

我需要这样的输出（在表格中）：

weeknr   tot dayhours   tot tvt hours
48       18              4.5
49       20              6.5
50       24              5.5

【问题讨论】：

嗯，问题是：我如何构建一个新的 foreach 来提供我想要实现的输出。 $array_dayhours 包含 weeknr 和 dayhours 但我还需要绑定到该周的 tvt 小时

请分享var_export($objs);的（样本），谢谢

【参考方案1】：

你可以这样做

$files = glob('data/*.json'); // all json files in array
$objs = [];
//array to store all data
$weeksData = [];

foreach($files as $file) 
        $objs[] = json_decode(file_get_contents($file), true); // decode to php assoc array             


foreach($objs as $key => $val) 
    
    //using weeknr as array key and pushing it to weekData array
    $weeksData[$val['weeknr']] = [
        'dayhours' => ($weeksData[$val['weeknr']]['dayhours'] ?? 0)  + $val['dayhours'],
        'tvt' => ($weeksData[$val['weeknr']]['tvt'] ?? 0) + $val['tvt']
    ];

【讨论】：

正是我要找的地方！ TNhx

【参考方案2】：

<?php
$files = glob('data*.txt'); // all json files in array
foreach($files as $file) 
    $objs[] = json_decode(file_get_contents($file), true); // decode to php assoc array

$arrayResult=[];
foreach($objs as $key => $val) 
    $weeknr = $val['weeknr']; // weeknr
    if(isset($arrayResult[$weeknr]) && is_array($arrayResult[$weeknr]))  // If already exist
        $arrayResult[$weeknr]=["weeknr"=>$val['weeknr'],"dayhours"=>$arrayResult[$weeknr]["dayhours"]+$val['dayhours'], "tvt"=>$arrayResult[$weeknr]["tvt"]+$val['tvt']];
    else // for new entry
        $arrayResult[$weeknr]=["weeknr"=>$val['weeknr'],"dayhours"=>$val['dayhours'], "tvt"=>$val['tvt']];

您可以使用 $arrayResult 进行打印