last.fm JSON data / how do I truncate this long array?

Question

I'm a bit of a novice with JSON. I'm working on building an events page using the JSON feed from last.fm.

The feed is working fine, but the issue is when multiple artists come across for the same event, such as a music festival. Right now the whole array is printing out with no spaces after the commas, and I can't figure out how to shorten the array if many bands are listed. (list the first ten bands, for example.)

The relevant part of my code is

$.getJSON(last_fm_url, function(data) {
  $.each(data.events.event, function(i, item){
    var eventTitle = item.title;
    var eventArtist = item.artists.artist;
  });
});

eventTitle is no big deal since there's only one, but I'm not sure what to do with eventArtist, how to separate that long list into individual items I can work with.

My sample is here: http://bit.ly/ZI4Q5h. My jsfiddle is here: http://jsfiddle.net/SBvUm/2/.

Thank you for your help.

Sorry–I've read this website many times but have never posted before. What's a self-contained example? — Anwar Montasir, Mar 13 '13 at 03:28
@AnwarMontasir you can make a http://jsfiddle.net or you can post the received json in the question body — Dakait, Mar 13 '13 at 03:45

guy mograbi · Accepted Answer · 2013-03-14T07:57:42.413

0

if you want 10 first items in an array you should use slice

 eventArtist = item.artists.artist.slice(0, 9);

I updated the jsfiddle : http://jsfiddle.net/SBvUm/3/

In order to control that "toString" array representation better, you can use "join".

For example : to get a space after each comma, your final code should look like this

 eventArtist = item.artists.artist.slice(0, 9).join(", ");

The problem you have is that sometimes item.artists.artist is not an array but a string. In this case, slice and join will not work properly.

Your code should look like this

updated the fiddle : http://jsfiddle.net/SBvUm/7/

 var eventArtist = item.artists.artist;
 if ( typeof(eventArtist["join"]) == "function"  ){
      eventArtist = eventArtist.slice(0,9).join(", ");
 }

edited Mar 14 '13 at 07:57

answered Mar 13 '13 at 19:06

guy mograbi

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Thanks @guymograbi, that answers half my question nicely. But how do I put spaces after each comma in the list? – Anwar Montasir Mar 13 '13 at 19:40
Ok, don't know if it's the most elegant solution, but I solved it: http://jsfiddle.net/SBvUm/4/. Thanks everybody. – Anwar Montasir Mar 14 '13 at 05:03
Just to answer your question in the comment - to control the separator on the array toString representation you should use "join". To get a comma with a space afterwards it will look like this `item.artists.artist.slice(0, 9).join(", ");` – guy mograbi Mar 14 '13 at 07:50
Ah. That's very helpful to know that item.artists.artist is sometimes an array and sometimes a string. I ended up using `instanceof Array` to test for it. http://jsfiddle.net/SBvUm/8/. – Anwar Montasir Mar 14 '13 at 21:00

last.fm JSON data / how do I truncate this long array?

1 Answers1