How can I parse a JSON file with PHP?

Question

I tried to parse a JSON file using PHP. But I am stuck now.

This is the content of my JSON file:

{
    "John": {
        "status":"Wait"
    },
    "Jennifer": {
        "status":"Active"
    },
    "James": {
        "status":"Active",
        "age":56,
        "count":10,
        "progress":0.0029857,
        "bad":0
    }
}

And this is what I have tried so far:

<?php

$string = file_get_contents("/home/michael/test.json");
$json_a = json_decode($string, true);

echo $json_a['John'][status];
echo $json_a['Jennifer'][status];

But because I don't know the names (like 'John', 'Jennifer') and all available keys and values (like 'age', 'count') beforehand, I think I need to create some foreach loop.

I would appreciate an example for this.

Answer 1

I can't believe so many people are posting answers without reading the JSON properly.

If you foreach iterate $json_a alone, you have an object of objects. Even if you pass in true as the second parameter, you have a two-dimensional array. If you're looping through the first dimension you can't just echo the second dimension like that. So this is wrong:

foreach ($json_a as $k => $v) {
   echo $k, ' : ', $v;
}

To echo the statuses of each person, try this:

<?php

$string = file_get_contents("/home/michael/test.json");
$json_a = json_decode($string, true);

foreach ($json_a as $person_name => $person_a) {
    echo $person_a['status'];
}

?>

Answer 2

Loop through the JSON with a foreach loop as key-value pairs. Do type-checking to determine if more looping needs to be done.

foreach($json_a as $key => $value) {
    echo $key;
    if (gettype($value) == "object") {
        foreach ($value as $key => $value) {
          # and so on
        }
    }
}

Answer 3

To iterate over a multidimensional array, you can use RecursiveArrayIterator

$jsonIterator = new RecursiveIteratorIterator(
    new RecursiveArrayIterator(json_decode($json, TRUE)),
    RecursiveIteratorIterator::SELF_FIRST);

foreach ($jsonIterator as $key => $val) {
    if(is_array($val)) {
        echo "$key:\n";
    } else {
        echo "$key => $val\n";
    }
}

Output:

John:
status => Wait
Jennifer:
status => Active
James:
status => Active
age => 56
count => 10
progress => 0.0029857
bad => 0

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