Some Core Javascript Functions

I recently worked on two different projects that involved a fair amount of Javascript centering around using the Google Maps API. In doing so I began to factor out some of the components to be reusable in a general Google Maps project. While I usually use the excellent Prototype Javascript library I didn't want to leak Prototype code into these reusable components. This led me to using these functions, borrowed / evolved from various places, as the core functions to support the components:

	if (!window.CAMBER) CAMBER = {};
	// create a bound function, forcing this
	CAMBER.createBoundFunction = function(object, method) {
	return function() {
	return method.apply(object, arguments);
	};
	};
	// constructor to create DOM element applying attributes and styles
	CAMBER.Element = function(tag, attrs, styles) {
	var elt = document.createElement(tag);
	CAMBER.Element.setAttrs(elt, attrs);
	CAMBER.Element.setStyle(elt, styles);
	return elt;
	};
	// beware cross browser issues {"class": "yourclass", className: "yourclass"}
	CAMBER.Element.setAttrs = function(elts, attrs) {
	if (!CAMBER.isArray(elts)) elts = [elts];
	attrs = attrs || {};
	for (var i = 0, l = elts.length; i < l; ++i) {
	for (var name in attrs) elts[i].setAttribute(name, attrs[name]);
	}
	};
	// set styles on elements
	CAMBER.Element.setStyle = function(elts, styles) {
	if (!CAMBER.isArray(elts)) elts = [elts];
	styles = styles || {};
	for (var i = 0, l = elts.length; i < l; ++i) {
	for (var style in styles) elts[i].style[style] = styles[style];
	}
	};
	// taken from http://tinyurl.com/8yew89
	CAMBER.isArray = function(obj) {
	return Object.prototype.toString.call(obj) === "[object Array]";
	};
	CAMBER.hasClassName = function(elt, className) {
	var regex = new RegExp("(^|\\s)" + className + "(\\s|$)");
	return regex.test(elt.className);
	};
	CAMBER.addClassName = function(elt, className) {
	if (!CAMBER.hasClassName(elt, className)) {
	elt.className += (elt.className ? " " : "") + className;
	}
	return elt;
	};
	CAMBER.removeClassName = function(elt, className) {
	var regex = new RegExp("(^|\\s)" + className + "(\\s|$)");
	elt.className = CAMBER.trim(elt.className.replace(regex, " "));
	return elt;
	};
	CAMBER.trim = function(str) {
	return str.replace(/^\s*|\s*$/g, "");
	};
	// taken from gmaps-utility-library
	CAMBER.getMousePosition = function(evt) {
	var posX = 0;
	var posY = 0;
	if (!evt) evt = window.event;
	if (evt.pageX || evt.pageY) {
	posX = evt.pageX;
	posY = evt.pageY;
	} else if (evt.clientX || evt.clientY){
	posX = evt.clientX +
	(document.documentElement.scrollLeft ? document.documentElement.scrollLeft : document.body.scrollLeft);
	posY = evt.clientY +
	(document.documentElement.scrollTop ? document.documentElement.scrollTop : document.body.scrollTop);
	}
	return {left: posX, top: posY};
	};
	// taken from gmaps-utility-library
	CAMBER.getElementPosition = function(elt) {
	var leftPos = elt.offsetLeft;
	var topPos = elt.offsetTop;
	var parElement = elt.offsetParent;
	while (parElement != null ) {
	leftPos += parElement.offsetLeft;
	topPos += parElement.offsetTop;
	parElement = parElement.offsetParent;
	}
	return {left: leftPos, top: topPos};
	};

view raw gistfile1.js hosted with ❤ by GitHub

I think these functions are a pretty good representation of the baseline support you will want in many Javascript projects.