通过它获取数组的索引值'；s值 - Get index value of an array by it's value in PHP from JSON file

Get index value of an array by it's value in PHP from JSON file

本文关键字：索引值获取数组 | 更新日期: 2023-09-27

我有这个数组结构，在发现我需要获得该数组的索引后，我想获得值为14的小时，我需要过滤其他元素，请帮助。

$string = file_get_contents("http://api.wunderground.com/api/aa433737d95d5869/hourly/q/US/Los%20Angeles%20International.json");
$json = json_decode($string, true);
foreach ($json as  $value) {
    echo "<pre>";
    print_r($value);
    echo "</pre>";
    print_r(search($value, 'hour', '14'));
    echo find_parent($value, '14');    
}

开始：

$json = json_decode($string, true);
foreach ($json['hourly_forecast'] as $key => $val) {
    if ($val['FCTTIME']['hour'] == 14) {
        die('The key is where hour is 14 is: ' . $key);
    }
}

您可以像这样使用foreach来获取每个key=>值对，并执行任何您想要的操作：

<?php
foreach ($json  as $key => $value) {
    if ($key === "hour") {
        if ($value === "14") {
            // do whatever
        }
    }    
}
?>

从您展示的api来看，您似乎需要对数组进行更深入的挖掘，但这就是您实现所需内容的方式。

我不确定我是否理解这个问题，但如果你想挑选hour等于14的FCTTIME项目，你可以这样做：

$json = file_get_contents("http://api.wunderground.com/api/aa433737d95d5869/hourly/q/US/Los%20Angeles%20International.json");
// decode the json string 
$object = json_decode($json);
// loop through each `hourly_forecast` item and check if `FCTTIME->hour` is equal to 14
foreach ($object->hourly_forecast as $index => $forecast) {
  if($forecast->FCTTIME->hour == 14) {
     // the $index contains the items position in the `hourly_forecast` array
  }
}