1.
<select id="s1" name="s1" onfocus="this.defaultIndex=this.selectedIndedx;" onchange="this.selectedIndex=this.defaultIndex;" />
2.
<select id="s1" name="s1" disabled="disabled" /> //用此方法时,提交表单前移除disabled属性,$("#s1").removeAttr("disabled");
3.
<select id="s1" name="s1" /> //在点击该下拉框时触发如下函数
$(function(){ $("#s1").click(function(){ alert("此处不可选择!"); return false; }); })