How to access the key itself using javascript

Question

I have a JSON:

  var xx = {'name':'alx','age':12};

Now I can read the value of name, which is "alx" as xx [0] .name, but how do I get the value of the name itself? By this I mean, how can I get the key at runtime?

Answer 1

for (i in xx) {
    if (xx[i] == "alx") {
        // i is the key
    }
}

Answer 2

modified code (from Victor), given that you can search for any other possible line

var search_object = "string_to_look_for";
for (i in xx) {
    if (xx[i] == search_object) {
        // i is the key 
        alert(i+" is the key!!!"); // alert, to make clear which one
    }
}

Answer 3

Javascript. Google :

Read this page http://www.quirksmode.org/js/associative.html

and especially this section http://www.quirksmode.org/js/associative.html#link5