jquery对话框的初始焦点

I am opening a jquery dialog box from a link in the HTML page. When the content of the dialog box is longer than the specified height of the box, the initial focus is at the bottom of the dialog box. (the specified height is not changeable -- this is used in a number of different places.) How do I get the focus to be at the top of the dialog box when it first opens?I am opening a jquery dialog box from a link in