event related object in javascript

var EventUtil = {

        addHandler: function (element, type, handler) {
            if (element.addEventListener) {
                element.addEventListener(type, handler, false);
            } else if (element.attachEvent) {
                element.attachEvent("on" + type, handler);
            } else {
                element["on" + type] = handler;
            }
        },

        removeHandler: function (element, type, handler) {
            if (element.removeEventListener) {
                element.removeEventListener(type, handler, false);
            } else if (element.detachEvent) {
                element.detachEvent("on" + type, handler);
            } else {
                element["on" + type] = null;
            }
        },

        getEvent: function (event) {
            return event ? event : window.event;
        },

        getTarget: function (event) {
            return event.target || event.srcElement;
        },

        preventDefault: function (event) {
            if (event.preventDefault) {
                event.preventDefault();
            } else {
                event.returnValue = false;
            }
        },

        stopPropagation: function (event) {
            if (event.stopPropagation) {
                event.stopPropagation();
            } else {
                event.cancelBubble = true;
            }
        },

        getRelatedTarget: function (event) {
            if (event.relatedTarget) {
                return event.relatedTarget;
            } else if (event.toElement) {
                return event.toElement;
            } else if (event.fromElement) {
                return event.fromElement;
            } else {
                return null;
            }
        },

        getButton: function (event) {
            if (document.implementation.hasFeature("MouseEvents", "2.0")) {
                return event.button;
            } else {
                switch (event.button) {
                    case 0:
                    case 1:
                    case 3:
                    case 5:
                    case 7:
                        return 0;
                    case 2:
                    case 6:
                        return 2;
                    case 4:
                        return 1;
                }
            }
        },

        getCharCode: function (event) {
            if (typeof event.charCode == "number") {
                return event.charCode;
            } else {
                return event.keyCode;
            }
        },

        getWheelDelta: function (event) {
            if (event.wheelDelta) {
                return (client.engine.opera && client.engine.opera < 9.5 ? -event.wheelDelta : event.wheelDelta);
            } else {
                return -event.detail * 40;
            }
        },

        getClipboardText: function (event) {
            var clipboardDate = (event.clipboardDate || window.clipboardDate);
            return clipboardDate.getDate("text");
        },

        setClipboardText: function (event, value) {
            if (event.clipboardDate) {
                return event.clipboardDate.setDate("text/plain", value);
            } else if (window.clipboardDate) {
                return window.clipboardDate.setDate("text", value);
            }
        }
    };