Question

Forgive me, I hope this question isn’t too obvious, I’m a javascript noob.

I have javascript code that takes numbers from an xml sheet and displays them in td elements on an html page. It works but I think it could be condensed into an array or a loop to be more efficient.

Is there a better way to write this code?

window.onload=function displayPrices()
{
twentyFourK=(x[i].getElementsByTagName("twentyFourK")[0].childNodes[0].nodeValue);
document.getElementById("twentyFourK").innerHTML=toCurrency(twentyFourK);

oneOzGold=(x[i].getElementsByTagName("oneOzGold")[0].childNodes[0].nodeValue);
document.getElementById("oneOzGold").innerHTML=toCurrency(oneOzGold);

fiveOzGold=(x[i].getElementsByTagName("fiveOzGold")[0].childNodes[0].nodeValue);
document.getElementById("fiveOzGold").innerHTML=toCurrency(fiveOzGold);

tenOzGold=(x[i].getElementsByTagName("tenOzGold")[0].childNodes[0].nodeValue);
document.getElementById("tenOzGold").innerHTML=toCurrency(tenOzGold);

oneKiloGold=(x[i].getElementsByTagName("oneKiloGold")[0].childNodes[0].nodeValue);
document.getElementById("oneKiloGold").innerHTML=toCurrency(oneKiloGold);

//etc.
}

Answer 1

Yes, a function could make things much easier for you:

window.onload = function() {
    function loadCurrency(name) {
        document.getElementById(name).innerHTML = toCurrency(x[i].getElementsByTagName(name)[0].firstChild.nodeValue);
    }

    loadCurrency('twentyFourK');
    loadCurrency('oneOzGold');
    loadCurrency('fiveOzGold');
    loadCurrency('tenOzGold');
    loadCurrency('oneKiloGold');
};

---

Also, if you have many items to load:

window.onload = function() {
    function loadCurrency(name) {
        document.getElementById(name).innerHTML = toCurrency(x[i].getElementsByTagName(name)[0].firstChild.nodeValue);
    }

    var items = ['twentyFourK', 'oneOzGold', 'fiveOzGold', 'tenOzGold', 'oneKiloGold'];
    items.forEach(loadCurrency);
};

That requires Array.forEach, which is only available in ECMAScript 5, so here’s a fallback:

Array.prototype.forEach = function(action, thisArg) {
    for(var i = 0, l = this.length; i < l; i++) {
        if(i in this) {
            action.call(thisArg, this[i], i, this);
        }
    }
};