一个常用的DIV弹出的jsp函数，可以控制div层的弹出位置以及弹出速度，并同时形成遮罩层，十分适合登陆等窗口的使用，避免跳转到新页面-A common jsp function pop-up DIV, you can control the position of div layer popup and pop-up speed, and also to form the mask layer is very suitable for landing window, to avoid jump to a new page