How Do I Access Data from JSON Using PHP?

How do I access data from JSON with PHP?

PHP provides the json_decode() function to decode a JSON string and convert it into a PHP data structure. Let’s dig into how to access the results:

Object property access:

Object properties can be accessed via $object->property For example:

$json = '{"type": "donut", "name": "Cake"}';
$yummy = json_decode($json);
echo $yummy->type; // "donut"

Array element access:

Array elements can be accessed through $array[0] For example:

$json = '["Glazed", "Chocolate with Sprinkles", "Maple"]';
$toppings = json_decode($json);
echo $toppings[1]; // "Chocolate with Sprinkles"

Nested item access:

Nested items can be accessed through consecutive attributes and indexes, such as $object-> array[0]->etc. :

$json = '{"type": "donut", "name": "Cake", "toppings": [{"id": "5002", "type": "Glazed"}]}';
$yummy = json_decode($json);
echo $yummy->toppings[0]->id; // "5002"

Convert to associative array:

Pass true as the second parameter of json_decode() to convert JSON The object is decoded into an associative array whose keys are strings:

$json = '{"type": "donut", "name": "Cake"}';
$yummy = json_decode($json, true);
echo $yummy['type']; // "donut"

Accessing the associative array items:

can be done via foreach (array_expression as $key => $ value) Traverse keys and values:

$json = '{"foo": "foo value", "bar": "bar value", "baz": "baz value"}';
$assoc = json_decode($json, true);
foreach ($assoc as $key => $value) {
    echo "The value of key '$key' is '$value'" . PHP_EOL;
}

Output:

The value of key 'foo' is 'foo value'
The value of key 'bar' is 'bar value'
The value of key 'baz' is 'baz value'

Unknown data structure:

If you don’t know the data structure, please refer to the related documentation or use print_r() Check the result:

print_r(json_decode($json));

json_decode() returns null:

This happens when the JSON is null or invalid. Use json_last_error_msg() to check error messages.

Special character attribute names:

Use {"@attributes":{"answer":42}} to access attribute names with special characters:

$json = '{"@attributes":{"answer":42}}';
$thing = json_decode($json);
echo $thing->{'@attributes'}->answer; //42

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