Why json_decode doesn't work? - php

Question

can somebody tell me where I'm making the error in the following code? I want to read the title of the 1 Position in the json Array.
<script>
$(document).ready(function(){
$('#loading').click(function(){
var NpPData = [
{
"title": "Professional JavaScript",
"author": "Nicholas C. Zakas"
},
{
"title": "JavaScript: The Definitive Guide",
"author": "David Flanagan"
},
{
"title": "High Performance JavaScript",
"author": "Nicholas C. Zakas"
}
];
var NpPDataJSON = JSON.stringify(NpPData);
alert(NpPDataJSON);
$.post("prueba.php", NpPDataJSON, function(r){
$('#result').html('Answer from server: '+r);
},
'json').error(function(e){
alert('FAiled: '+e.statusText);
});
});
});
</script>
And PHP:
$json = $_POST['NpPDataJSON'];
$data = json_decode($json);
echo $data[1]['title'];

Answer 1

Set second parameter to TRUE to have json_decode() to return an array instead of an stdClass object:
$json = $_POST['NpPDataJSON'];
$data = json_decode($json, true); // note the second argument
echo $data[1]['title']; // returns 'JavaScript: The Definitive Guide'
When TRUE, returned objects will be converted into associative arrays.
Also, as per #Stryner's comment, it seems you have misused the $.post() function. You need to set a name to the data you are passing to the server and therefore, pass an object instead of a variable:
$.post("prueba.php", {NpPDataJSON: NpPDataJSON}, function(r){/* ... */}, 'json');