a标签href非链接与beforeunload冲突有关问题

<a id="submit_btn" href="javascript:void(0)" class="easyui-linkbutton" icon="icon-ok" plain="true">提交</a>

$(window).bind('beforeunload',function(){
     return '你确定要退出系统快吗？';
});
		
$('#submit_btn').click(function() {
     //提交
});

<a id="submit_btn" href="#this" class="easyui-linkbutton" icon="icon-ok" plain="true">提交</a>

		
$('#submit_btn').click(function() {
     //提交
     return false;
});