<select id = "list" >
<option tips="1">公告</option>
<option tips="2">活动</option>
<option tips="3">版本</option>
</select>
<input id="intro" type="text" name="type">
var oSelect = document.getElementById("list");
var oInput = document.getElementById("intro");
oInput.value = $("#list").find("option:selected").attr("tips");
oSelect.onchange = function(e){
var opt = this.options[this.options.selectedIndex];
oInput.value = opt.getAttribute("tips");
}
默认显示也为自定义标签的值