如何从json访问对象以自动下拉

Question

I have been trying for a while now to access the contents of a json object. I am using jQuery to try and automate a dropdown.

---

Here is the json code

{
"Kingston":
{
  "tots": [
    "9.15-10.00am"
  ],
  "kickers": [
    "9.15-10.00am"
  ],
  "strikers": [
    "9.15-10.00am"
  ],
  "academy": [
    "9.15-10.00am"
  ]
}
,
"Knaphill":
{
  "tots": [
    "9.15-10.00am"
  ],
  "kickers": [
    "9.15-10.00am"
  ],
  "strikers": [
    "9.15-10.00am"
  ],
  "academy": [
    "9.15-10.00am"
  ]
}
}

Here is what I have so far for the javascript. It keeps giving me an undefined error.

jQuery( document ).ready(function() {
console.log("ready");
$.getJSON("sessions.json", function(data) {
    var key = <?php echo json_encode($form->data['hb_venue']); ?>;
    var cat = "tots";
    var c = [];
    switch (key) {
        case "Kingston":
            c = data.Kingston.cat.split(",");
            break;
        default:
            c = '<option>Choose a class</option>';
    }
    var $sessList = $("#cb_sessions");
    $sessList.empty();
    $.each(c, function(index, value) {
    $sessList("<option>" + value + "</option>");
    });
});
});

Answer 1

You have to realise that JSON works as an array (or objects) of objects.

The reason you are getting an undefined error is because u are accessing your object wrongly.

This code c = data.Kingston.cat.split(","); is wrong because it is equivalent to doing this:

c = data.Kingston."tots".split(",");

That is the wrong way to access the object. This is the correct way:

c = data["Kingston"][cat][0].split(",");

EDIT: the reason for the extra [0] is because data["Kingston"][cat] returns an object, so to access the string in the object, you have to access it by data["Kingston"][cat]

Answer 2

To get your values, you should probably do something like this:

data.Kingston.tots
data.Kingston.kickers
data.Kingston.strikers
data.Kingston.academy