Question

my json string is as follows:

var data = [{"first":"3","second":"1"},{"first":"5","second":"5"},{"first":"7","second":"1"}];

Now i am calling –

objx(data).collect("first") 

and expecting to get an array like [3,5,7].
But i am getting javascript error : object doesn’t support this property or method.
i have tried with

objx(data).collect("first").obj() but with no avail.

i have included objx-2.3.6.js file from http://code.google.com/p/objx/ and i want to create the array with objx api to reduce no of lines of code.
i am using IE8

please suggest a way out.

Answer 1

“my json string” – That’s neither JSON nor a string. Anyway…

Since you’ve tagged your question with jQuery (even though you don’t mention it in your question anywhere) here is a jQuery solution to the same problem:

var fields = $.map(data, function(val) { return val.field; });
// fields is [3,5,7]

As far as why you’re getting the particular error you do, that would be because the .collect() method is not part of the core objx library, at least, it is not in objx-2.3.6.js. Presumably you need to include the Collections plugin js too (but I couldn’t find it).