Get data from JSON.parse from ajax call

Question

I've been looking everywhere for the answer.

I have the JSON string

"[{"id":"0"}]"

I've tried

obj['id'] and obj.id

but that doesn't work

    $.ajax({
        url: 'php/checkdoctorappointmentonday.php',
        data: 'doctorName=' + doctorName + '&dayOfEvent=' + date1,
        type: "POST",
        success: function (json) {
            obj = JSON.parse(json.data)[0];
            b = obj.id;
        }
    });
    return true;
}

Am I missing anything?

This is the php used to get the result Edit:

    <?php
$doctorName = $_POST['doctorName'];
$dayOfEvent = $_POST['dayOfEvent'];


// Query that retrieves events
$query = "SELECT COUNT(id) AS 'id'
            FROM doctoravailability
            WHERE start >='$dayOfEvent' AND start < DATE_ADD('$dayOfEvent', INTERVAL 1 DAY)
            AND title = '$doctorName'
            AND backgroundColor = 'red'
          ";

// connection to the database
try {
    $bdd = new PDO("mysql:host=$servername;dbname=$dbname",$username,$password);
} catch(Exception $e) {
    exit('Unable to connect to database.');
}
// Execute the query
$resultat = $bdd->query($query) or die(print_r($bdd->errorInfo()));

// sending the encoded result to success page
echo json_encode($resultat->fetchAll(PDO::FETCH_ASSOC));

?>

Answer 1

Does your JSON string actually have the start and end " in it, or have you just added them there to illustrate that it is a string?

Assuming that our data string actually has the ", then you just want to use the syntax

[{"id":"0"}]

Answer 2

As per comments, the object is actually an array containing an object

var str = "[{\"id\":\"0\"}]";
var obj = JSON.parse(str)[0];
alert(obj.id);

http://jsfiddle.net/6ae0bgag/

obj["id"] would have also worked, its the same as obj.id

Answer 3

Try this:

JS

$.ajax({
        url: 'php/checkdoctorappointmentonday.php',
        data: {
            doctorName: doctorName,
            dayOfEvent: date1
        },      
        type: "POST",
        dataType: 'json',
        success: function (data) {
            console.log(data);
            b = data.0.id;
        }
    });

PHP

<?php
    $doctorName = $_POST['doctorName'];
    $dayOfEvent = $_POST['dayOfEvent'];


    // Query that retrieves events
    $query = "SELECT COUNT(id) AS 'id'
                FROM doctoravailability
                WHERE start >='$dayOfEvent' AND start < DATE_ADD('$dayOfEvent', INTERVAL 1 DAY)
                AND title = '$doctorName'
                AND backgroundColor = 'red'
              ";

    // connection to the database
    try {
        $bdd = new PDO("mysql:host=$servername;dbname=$dbname",$username,$password);
    } catch(Exception $e) {
        exit('Unable to connect to database.');
    }
    // Execute the query
    $resultat = $bdd->query($query) or die(print_r($bdd->errorInfo()));

    // sending the encoded result to success page
    return $resultat->fetchAll(PDO::FETCH_ASSOC);
?>