FormChangesDetector.js

/**
 * Checks if changes are made to a form
 * credits to Craig Buckler "http://www.sitepoint.com/javascript-form-change-checker/"
 * @param {type} form
 * @returns {Array|formChanges.changed}
 */
function IsFormChanged(form) {
    if (typeof(form) === "string"){
        form = document.getElementById(form);
    }
    
    if (!form || !form.nodeName || form.nodeName.toLowerCase() !== "form"){
        return null;
    }
    
    var changed = [], n, c, def, o, ol, opt;
    
    for (var e = 0, el = form.elements.length; e < el; e++) {
        n = form.elements[e];
        c = false;
        
        switch (n.nodeName.toLowerCase()) {

            // select boxes
            case "select":
                def = 0;
                
                for (o = 0, ol = n.options.length; o < ol; o++) {
                    opt = n.options[o];
                    c = c || (opt.selected !== opt.defaultSelected);
                    if (opt.defaultSelected){
                        def = o;
                    }
                }
                
                if (c && !n.multiple){
                    c = (def !== n.selectedIndex);
                }
                break;
                
            //input/textarea
            case "textarea":
            case "input":

                switch (n.type.toLowerCase()) {
                    case "checkbox":
                    case "radio":
                    
                    // checkbox / radio
                    c = (n.checked !== n.defaultChecked);
                    break;
                    
                    default:
                    // standard values
                    c = (n.value !== n.defaultValue);
                    break;
                }
                
                break;
        }

        if (c){
            changed.push(n);
        }
    }
    
    
    //return true or false based on the length of variable "changed"
    if(changed.length > 0){
        return true;
    }
    
    else{
        return false;
    }
}