全局监听enter回车事件

        document.onkeydown = keydown;
        function keydown(e) 
        {
           var currKey=0,e=e||event; 
           currKey=e.keyCode||e.which||e.charCode;//支持IE、FF 
           if (currKey == 13){
              that.searchSub();
           }
        }

//监听事件    参考资料