取消图片的默认事件

//取消图片的默认行为
    $(function(){
    var $img = $("img");
    var moving = function(event){
        //something
    }
    
    var img = document.getElementsByTagName(‘img‘);
    //IE下需要在document的mousemove里面取消默认事件;要用原生JS的事件不能用JQuery
    for (var i = 0; i < img.length; i++) {
        img[i].onmousemove = function(e){
            var ev = e || event;
            ev.cancelBubble=true;
            ev.returnValue = false;
        };
    }
    
    
    $img.mousedown(function(event){
        //FF下需要在mousedown取消默认操作;
        event.preventDefault();
        event.stopPropagation();
        $(this).bind("mousemove",moving);    
    })
})