Reading Dynamic JSON Array

Question

I trying to build a JavaScript function which will grab a JSON encoded array and return a value based on the requested key. I use the jQuery $.parseJSON() method to take the JSON string and convert it into a JavaScript object. Here a watered down example:

function getValue(dynamicArrayKey) {
  var theArray = $.parseJSON(/* Get some JSON from a source using jQuery */);

  alert('Here is the value: ' + theArray.dynamicArrayKey);
}

So the key I want will be given to the function, and it should return the resulting value. I am thinking that the JavaScript eval() method should be used in there somewhere, but I'm not sure. Any help would be greatly appreciated.

score 4 · Accepted Answer · answered Apr 11 '11 at 22:48

4

There's no need to eval(), use

alert('Here is the value: ' + theArray[dynamicArrayKey]);

answered Apr 11 '11 at 22:48

Dr.Molle

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Awesome! Works like a charm! I was wondering, though, why can I do something like this: "theArray.notDynamicArrayKay", when I'm actually looking for a key by that name, but I have to use the "theArray[dynamicArrayKey]" when the value I'm looking for a value that is dynamic? Just curious. – Oliver Spryn Apr 11 '11 at 22:51
1

It's called subscript notation. You may take a look at http://www.crockford.com/misty/objects.html :) – Dr.Molle Apr 11 '11 at 23:03

score 0 · Answer 2 · edited May 23 '17 at 10:33

0

Take a look at this. It may help.

How to search JSON tree with jQuery

edited May 23 '17 at 10:33

Community

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answered Apr 11 '11 at 22:49

Diodeus - James MacFarlane

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Thanks for the pointer, but I'm afraid that would involve too much redundant processing for a simple task, especially since this function will be called rather frequently. – Oliver Spryn Apr 11 '11 at 22:55

Reading Dynamic JSON Array

2 Answers2