<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>下拉框</title>
<style>
* {
    margin: 0;
    padding: 0;
}
     
body {
    padding: 50px 50px;
}
     
.btn-select {
    position: relative;
    display: inline-block;
    width: 150px;
    height: 25px;
    background-color: #f80;
    font: 14px/20px "Microsoft YaHei";
    color: #fff;
}
     
.btn-select .cur-select {
    position: absolute;
    display: block;
    width: 150px;
    height: 25px;
    line-height: 25px;
    background: #f80 url(ico-arrow.png) no-repeat 125px center;
    text-indent: 10px;
}
     
.btn-select:hover .cur-select {
    background-color: #f90;
}
     
.btn-select select {
    position: absolute;
    top: 0;
    left: 0;
    width: 150px;
    height: 25px;
    opacity: 0;
    filter: alpha(opacity: 0;);
    font: 14px/20px "Microsoft YaHei";
    color: #f80;
}
     
.btn-select select option {
    text-indent: 10px;
}
     
.btn-select select option:hover {
    background-color: #f80;
    color: #fff;
}
</style>
</head>
<body>
	<form>
<a class="btn-select" id="btn_select">
    <span class="cur-select">请选择</span>
    <select>
        <option>选项一</option>
        <option>选项二</option>
        <option>选项三</option>
        <option>选项四</option>
        <option>选项五</option>
    </select>
</a>
</form>
<script>
	var $$ = function (id) {
    return document.getElementById(id);
}
window.onload = function () {
    var btnSelect = $$("btn_select");
    var curSelect = btnSelect.getElementsByTagName("span")[0];
    var oSelect = btnSelect.getElementsByTagName("select")[0];
    var aOption = btnSelect.getElementsByTagName("option");
    oSelect.onchange = function () {
        var text=oSelect.options[oSelect.selectedIndex].text;
        curSelect.innerHTML = text;
    }
}
</script>
</body>
</html>
原文:http://www.cnblogs.com/amandaff/p/4022848.html