php - Find the number of objects in a json array

Question

I have searched a lot and I found few methods to find the length of my JSON array. I have tried:

1. count
2. json.length

but these return 1, instead of the actual length. I want to show it using PHP.

My json is:

$huge = '[{"location":[{"building":["Default Building"],"name":"Default Location"}],"name":"Default Organization"},{"location":[{"building":["test_loc1_building1","test_loc1_building2"],"name":"test location1"},{"building":["test_loc2_building2"],"name":"test location2"}],"name":"test Organization"}]';

How can I find the number of objects in my JSON array?

Answer 1

您需要解码 json对象，然后计算其中的元素..

 $json_array  = json_decode($json_string, true);
 $elementCount  = count($json_array);

Answer 2

You'll need to decode into PHP arrays before you do any work with the data.

Try:

$hugeArray = json_decode($huge, true); // Where variable $huge holds your JSON string.

echo count($hugeArray);

If you need to count to a lower depth, you'll need to iterate through the array.

For example, if you want to count the number of elements in the next layer, you can do:

foreach ($hugeArray as $key => $value) {
    echo $key.' - '.count($value);
}

However, this isn't necessarily meaningful because it depends on what you are trying to count, what your goal is. This block only counts the number of elements 1 layer underneath, regardless of what the actual numbers could mean.

Answer 3

首先解码你的json，然后使用count它。

$huge='[{"location":[{"building":["Default Building"],"name":"Default Location"}],"name":"Default Organization"},{"location":[{"building":["test_loc1_building1","test_loc1_building2"],"name":"test location1"},{"building":["test_loc2_building2"],"name":"test location2"}],"name":"test Organization"}]';
$arr = json_decode($huge,true);
echo count($arr);

Answer 4

对象（key:value 对的无序集合，使用 ':' 字符分隔键和值，以逗号分隔并用大括号括起来；...）

维基百科：JSON

所以，你所要做的只是计算打开的花括号。

substr_count($huge , '{');

但是......如果你在 json 中存储一些带有 '{' 的字符串，你就不能这样做。这样，您必须编写自己的简单解析器或正则表达式。

但是...... json_decode 的简单方法。如果要获取json中所有对象的计数，请使用递归函数。

function count_objects($value)
    {
    if (is_scalar($value) || is_null($value))
        $count = 0;
    elseif (is_array($value))
        {
        $count = 0;
        foreach ($value as $val)
            $count += count_objects($val);
        }
    elseif (is_object($value))
        {
        $count = 1;
        $reflection_object = new \ReflectionObject($value);
        foreach ($reflection_object->getProperties() as $property)
            {
            $count +=count_objects($property->getValue($value));
            }
        }

    return $count;
    }

$huge = '[{"location":[{"building":["Default Building"],"name":"Default Location"}],"name":"Default Organization"},{"location":[{"building":["test_loc1_building1","test_loc1_building2"],"name":"test location1"},{"building":["test_loc2_building2"],"name":"test location2"}],"name":"test Organization"}]';

echo count_objects(json_decode($huge));

Answer 5

我们可以使用“.sizeof()”函数。所以