Traverse all the Nodes of a JSON Object Tree with JavaScript

Question

I'd like to traverse a JSON object tree, but cannot find any library for that. It doesn't seem difficult but it feels like reinventing the wheel.

In XML there are so many tutorials showing how to traverse an XML tree with DOM :(

Answer 1

If you think jQuery is kind of overkill for such a primitive task, you could do something like that:

//your object
var o = { 
    foo:"bar",
    arr:[1,2,3],
    subo: {
        foo2:"bar2"
    }
};

//called with every property and its value
function process(key,value) {
    console.log(key + " : "+value);
}

function traverse(o,func) {
    for (var i in o) {
        func.apply(this,[i,o[i]]);  
        if (o[i] !== null && typeof(o[i])=="object") {
            //going one step down in the object tree!!
            traverse(o[i],func);
        }
    }
}

//that's all... no magic, no bloated framework
traverse(o,process);