var ClassNameUtil={ hasClassName: function(obj, psClass) { if (obj && obj.className) { var classes = obj.className.split(/\s+/); for (var i = 0; i < classes.length; i++) { if (psClass == classes[i]) { return i + 1; // use 1-based index to return 0 for false } } } return 0; }, addClassName: function(obj, psClass) { if (this.hasClassName(obj, psClass)) { return; } if (obj && obj.className) { var classes = obj.className.split(/\s+/); obj.className = classes.push(psClass).join(' '); } }, removeClassName: function(obj, psClass) { var i; if (i = this.hasClassName(obj, psClass)) { var classes = obj.className.split(/\s+/); var newClasses = []; for (var i = 0; i < old.length; i++) { if (psClass !== old[i]) { newClasses.push(old[i]); } } obj.className = newClasses.join(' '); } return; }};