Consuming JSON with JavaScript

Question

I'm trying to read this link.

http://wsloterias.azurewebsites.net/api/sorteio/getresultado/1

with this method:

$.getJSON(" http://wsloterias.azurewebsites.net/api/sorteio/getresultado/1",function (json) {
    alert(json.length);
});

But it doesn't work, and I don't know the reason :(

Some one can help me?

[edit]

I just want to read, the "json.length" its was just a test. I tried this with another .json, and worked. I want to know if a need to use some method that read without problems.

@CiroCorvino Try `{}.length`, Whatever error you get is the same error. — Praveen Kumar Purushothaman, Dec 24 '16 at 18:08
@procrastinator When I know the answer, why the wait? Is it wrong? — Praveen Kumar Purushothaman, Dec 24 '16 at 18:09
@PraveenKumar Bekoz : 1. you look like flash gordon 2. i edited my comment to make it closer to my thoughts. — , Dec 24 '16 at 18:11
@procrastinator I am Canvas Gordon (flash is not supported in HTML5). — Praveen Kumar Purushothaman, Dec 24 '16 at 18:11
@PraveenKumar if the error it is a json empty array as you argue, the first space before the address of the service maybe can create some problem to the ajax Jquery call done by getJSON — Ciro Corvino, Dec 24 '16 at 18:11
Start by understanding the data structure you are working with. go through the detailed explanation/tutorial in linked question — charlietfl, Dec 24 '16 at 18:12
@charlietfl The comment for who? Me or OP? Is my answer right? I am planning to remove if it is not right. — Praveen Kumar Purushothaman, Dec 24 '16 at 18:13
@CiroCorvino Is my answer right? I am planning to remove if it is not right. — Praveen Kumar Purushothaman, Dec 24 '16 at 18:14
@charlietfl Also, I don't understand how this question is a dupe of that question. Do you mind explaining it? — Praveen Kumar Purushothaman, Dec 24 '16 at 18:17
@PraveenKumar question is so vague and really just asks how to read the data. No idea what they want from it, it's not clear. So the fundamentals are well detailed in duplicate — charlietfl, Dec 24 '16 at 18:18
Oh okay... I feel I can easily find the issue OP is facing... The OP also mentioned that they don't know English. So it might be a reason too. — Praveen Kumar Purushothaman, Dec 24 '16 at 18:22
I just want to read, the "json.length" its was just a test. I tried this with another .json, and worked. I want to know if a need to use some method that read without problems. — Joao Henrique, Dec 24 '16 at 19:32

Praveen Kumar Purushothaman · Answer 1 · 2016-12-24T18:15:17.470

If the variable fetched is an object, instead of array, you need to use Object.keys(), which gives you the list of keys as an array and you can use the .length on it:

$.getJSON("http://wsloterias.azurewebsites.net/api/sorteio/getresultado/1", function(json) {
  alert(Object.keys(json).length);
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

One thing I noticed is, the following URL:

http://wsloterias.azurewebsites.net/api/sorteio/getresultado/1

Doesn't have the CORS enabled. So, if you try accessing it, it throws an error in the Console, which is kinda silent. If you mean that, you need to request or make the JSON to have CORS Enabled.

Consuming JSON with JavaScript

1 Answers1