本文实例讲述了JS+CSS实现美化的下拉列表框效果。分享给大家供大家参考。具体如下：
一款经过JS+CSS美化的下拉列表，效果很不错，但代码有点偏多，学习CSS的朋友可以学习一下方法，然后自己变通一下，把代码简化一下。
运行效果如下图所示：
具体代码如下：
<!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=gb2312" />
<title>JS+CSS下拉列表</title>
<style type="text/css">
body{
font-size:12px; margin:0
}
.center{ margin-left:auto; margin-right:auto; margin-top:200px; width:300px;}
#age_sel_2 div.tag_select{display:block;color:#000;width:62px;height:22px;background:transparent url("//img.jbzj.com/file_images/article/201508/2015811145849095.gif") no-repeat 0 0;padding:0 10px;line-height:22px;}
#age_sel_2 div.tag_select_hover{display:block;color:#000;width:62px;height:22px;background:transparent url("//img.jbzj.com/file_images/article/201508/2015811145849095.gif") no-repeat 0 -22px;padding:0 10px;line-height:22px;}
#age_sel_2 div.tag_select_open{display:block;color:#000;width:62px;height:22px;background:transparent url("//img.jbzj.com/file_images/article/201508/2015811145849095.gif") no-repeat 0 -44px;padding:0 10px;line-height:22px;}
#age_sel_2 ul.tag_options{position:absolute;margin:0;list-style:none;background:transparent url("//img.jbzj.com/file_images/article/201508/2015811145849095.gif") no-repeat left bottom;padding:0 0 1px;margin:0;width:60px;}
#age_sel_2 ul.tag_options li{background:transparent url("//img.jbzj.com/file_images/article/201508/2015811145849095.gif") repeat-y -102px 0;display:block;width:61px;padding:0 10px;height:22px;text-decoration:none;line-height:22px;color:#000;}
#age_sel_2 ul.tag_options li.open_hover{background:transparent url("//img.jbzj.com/file_images/article/201508/2015811145849095.gif") no-repeat 0 -88px;color:#000}
#age_sel_2 ul.tag_options li.open_selected{background:transparent url("//img.jbzj.com/file_images/article/201508/2015811145849095.gif") no-repeat 0 -66px;color:#19555F}
</style>
<script>
var selects = document.getElementsByTagName('select');
var isIE = (document.all && window.ActiveXObject && !window.opera) ? true : false;
function $(id) {
return document.getElementById(id);
}
function stopBubbling (ev) {
ev.stopPropagation();
}
function rSelects() {
for (i=0;i<selects.length;i++){
selects[i].style.display = 'none';
select_tag = document.createElement('div');
select_tag.id = 'select_' + selects[i].name;
select_tag.className = 'select_box';
selects[i].parentNode.insertBefore(select_tag,selects[i]);
select_info = document.createElement('div');
select_info.id = 'select_info_' + selects[i].name;
select_info.className='tag_select';
select_info.style.cursor='pointer';
select_tag.appendChild(select_info);
select_ul = document.createElement('ul');
select_ul.id = 'options_' + selects[i].name;
select_ul.className = 'tag_options';
select_ul.style.position='absolute';
select_ul.style.display='none';
select_ul.style.zIndex='999';
select_tag.appendChild(select_ul);
rOptions(i,selects[i].name);
mouseSelects(selects[i].name);
if (isIE){
selects[i].onclick = new Function("clickLabels3('"+selects[i].name+"');window.event.cancelBubble = true;");
}
else if(!isIE){
selects[i].onclick = new Function("clickLabels3('"+selects[i].name+"')");
selects[i].addEventListener("click", stopBubbling, false);
}
}
}
function rOptions(i, name) {
var options = selects[i].getElementsByTagName('option');
var options_ul = 'options_' + name;
for (n=0;n<selects[i].options.length;n++){
option_li = document.createElement('li');
option_li.style.cursor='pointer';
option_li.className='open';
$(options_ul).appendChild(option_li);
option_text = document.createTextNode(selects[i].options[n].text);
option_li.appendChild(option_text);
option_selected = selects[i].options[n].selected;
if(option_selected){
option_li.className='open_selected';
option_li.id='selected_' + name;
$('select_info_' + name).appendChild(document.createTextNode(option_li.innerHTML));
}
option_li.onmouseover = function(){ this.className='open_hover';}
option_li.onmouseout = function(){
if(this.id=='selected_' + name){
this.className='open_selected';
}
else {
this.className='open';
}
}
option_li.onclick = new Function("clickOptions("+i+","+n+",'"+selects[i].name+"')");
}
}
function mouseSelects(name){
var sincn = 'select_info_' + name;
$(sincn).onmouseover = function(){ if(this.className=='tag_select') this.className='tag_select_hover'; }
$(sincn).onmouseout = function(){ if(this.className=='tag_select_hover') this.className='tag_select'; }
if (isIE){
$(sincn).onclick = new Function("clickSelects('"+name+"');window.event.cancelBubble = true;");
}
else if(!isIE){
$(sincn).onclick = new Function("clickSelects('"+name+"');");
$('select_info_' +name).addEventListener("click", stopBubbling, false);
}
}
function clickSelects(name){
var sincn = 'select_info_' + name;
var sinul = 'options_' + name;
for (i=0;i<selects.length;i++){
if(selects[i].name == name){
if( $(sincn).className =='tag_select_hover'){
$(sincn).className ='tag_select_open';
$(sinul).style.display = '';
}
else if( $(sincn).className =='tag_select_open'){
$(sincn).className = 'tag_select_hover';
$(sinul).style.display = 'none';
}
}
else{
$('select_info_' + selects[i].name).className = 'tag_select';
$('options_' + selects[i].name).style.display = 'none';
}
}
}
function clickOptions(i, n, name){
var li = $('options_' + name).getElementsByTagName('li');
$('selected_' + name).className='open';
$('selected_' + name).id='';
li[n].id='selected_' + name;
li[n].className='open_hover';
$('select_' + name).removeChild($('select_info_' + name));
select_info = document.createElement('div');
select_info.id = 'select_info_' + name;
select_info.className='tag_select';
select_info.style.cursor='pointer';
$('options_' + name).parentNode.insertBefore(select_info,$('options_' + name));
mouseSelects(name);
$('select_info_' + name).appendChild(document.createTextNode(li[n].innerHTML));
$( 'options_' + name ).style.display = 'none' ;
$( 'select_info_' + name ).className = 'tag_select';
selects[i].options[n].selected = 'selected';
}
window.onload = function(e) {
bodyclick = document.getElementsByTagName('body').item(0);
rSelects();
bodyclick.onclick = function(){
for (i=0;i<selects.length;i++){
$('select_info_' + selects[i].name).className = 'tag_select';
$('options_' + selects[i].name).style.display = 'none';
}
}
}</script>
</head>
<body>
<div class="center">
<div id="age_sel_2">
<select name="area_selet2" id="area_select2">
<option value="请选择">请选择</option>
<option value="ASP" >ASP</option>
<option value="PHP" >PHP</option>
<option value=".NET" >.NET</option>
<option value="Csharp" >Csharp</option>
<option value="Delphi" >Delphi</option>
<option value="Java" >Java</option>
</select>
</div>
</div>
</body>
</html>
希望本文所述对大家的javascript程序设计有所帮助。
