Testing for an empty array object in JSON with jQuery

Question

I have a request that returns a JSON object with a single property which is an array. How can I test if the array is empty?

With jQuery code like:

 $.getJSON(
            jsonUrl,
            function(data) {
                if (data.RoleOwners == [ ]) {
                    $('<tr><td>' + noRoleOwnersText + '</td></tr>').appendTo("#roleOwnersTable tbody");
                    return;
                }
                $.each(data.RoleOwners, function(i, roleOwner) {
                    var tblRow =
                    "<tr>"
                    + "<td>" + roleOwner.FirstName + "</td>"
                    + "<td>" + roleOwner.LastName + "</td>"
                    + "</tr>"
                    $(tblRow).appendTo("#roleOwnersTable tbody");
                });

what can I put instead of if(data.RoleOwners == [ ]) to test if the RoleOwners is an empty array?

Thanks, Matt

Answer 1

(data.RoleOwners.length === 0)

Answer 2

You can also do jQuery.isEmptyObject(data.RoleOwners)

check out http://api.jquery.com/jQuery.isEmptyObject/

Answer 3

below code works perfectly fine no need to write one of yours own.

   // anyObjectIncludingJSON i tried for JSON object.

         if(jQuery.isEmptyObject(anyObjectIncludingJSON))
            {
                return;
            }

Answer 4

Check this

JSON.parse(data).length > 0