JSFiddle - React, Tailwind, and code Playground

by chim

HTML

<div id="y"></div>
<div id="n"></div>

JavaScript

var test = {
    categories: {category: {category: {category : {CATEGORYNAME: 'WAT'}}}}
};

// document.body.innerHTML = test.categories.category.category.category.CATEGORYNAME;

function myJsonValue(ob, prop) {
    var propsArray = prop.split('.');
    var out = ob;
    for (i in propsArray){
        var dis = propsArray[i];
        if (!out[dis]) {
            return null;
        }
        out = out[dis];
    }
    return out;
}

document.getElementById('y').innerHTML = myJsonValue(test, "categories.category.category.category.CATEGORYNAME"); // WAT

document.getElementById('n').innerHTML = myJsonValue(test, "categories.category.category.category.DOESNT_EVEN"); // null