ajax.js
/**
* ajax无刷新二级联动下拉菜单(省市联动)
*
* @author arcow <arcow@126.com>
* @version 1.0
* @lastupdate 2005-12-29
*
*/
var http_request = false;
function send_request(url,method) {//初始化、指定处理函数、发送请求的函数
http_request = false;
//开始初始化XMLHttpRequest对象
if(window.XMLHttpRequest) { //Mozilla 浏览器
http_request = new XMLHttpRequest();
if (http_request.overrideMimeType) {//设置MiME类别
http_request.overrideMimeType('text/xml');
}
}
else if (window.ActiveXObject) { // IE浏览器
try {
http_request = new ActiveXObject("Msxml2.XMLHTTP");
} catch (e) {
try {
http_request = new ActiveXObject("Microsoft.XMLHTTP");
} catch (e) {}
}
}
if (!http_request) { // 异常，创建对象实例失败
window.alert("不能创建XMLHttpRequest对象实例.");
return false;
}
switch(method){
case 1: http_request.onreadystatechange = processRequest1;break;//选择操作函数
case 2: http_request.onreadystatechange = processRequest2;break;
case 3: http_request.onreadystatechange = processRequest3;break;
}
// 确定发送请求的方式和URL以及是否同步执行下段代码
http_request.open("GET", url, true);
http_request.send(null);
}
// 处理返回信息的函数
function processRequest1() {//操作函数1,调入省
if (http_request.readyState == 4) { // 判断对象状态
if (http_request.status == 200) { // 信息已经成功返回，开始处理信息
document.getElementById("statusTxt").innerHTML="";
addOptionGroup("province",http_request.responseText);
} else { //页面不正常
alert("您所请求的页面有异常。");
}
}else {//只要未读取完成
document.getElementById("statusTxt").innerHTML="正则读取数据中……";
}
}
function processRequest2() {//操作函数2,调入市
if (http_request.readyState == 4) { // 判断对象状态
if (http_request.status == 200) { // 信息已经成功返回，开始处理信息
document.getElementById("statusTxt").innerHTML="";
addOptionGroup("city",http_request.responseText);
} else { //页面不正常
alert("您所请求的页面有异常。");
}
}else {//只要未读取完成
document.getElementById("statusTxt").innerHTML="正则读取数据中……";
}
}
function processRequest3() {//操作函数3,输入省市
if (http_request.readyState == 4) { // 判断对象状态
if (http_request.status == 200) { // 信息已经成功返回，开始处理信息
document.getElementById("statusTxt").innerHTML="";
document.getElementById("district").value=http_request.responseText;
} else { //页面不正常
alert("您所请求的页面有异常。");
}
}else {//只要未读取完成
document.getElementById("statusTxt").innerHTML="正则读取数据中……";
}
}
function loadProvince() {//载入省
send_request("select.server.php?action=province",1);//服务端处理程序,操作函数
}
function loadCity() {//载入市
document.getElementById("district").value="";//清空文本框
send_request("select.server.php?action=city&id="+document.getElementById("province").value,2);
}
function inputDistrict() {//向文本框输入选定的省市
send_request("select.server.php?action=district&id="+document.getElementById("province").value+"&id1="+document.getElementById("city").value,3);
}
addOption.js
function addOption(objSelectNow,txt,val)
{
/// 使用W3C标准语法为SELECT添加Option
var objOption = document.createElement("OPTION");
objOption.text= txt;
objOption.value=val;
objSelectNow.options.add(objOption);
}
function addOptionGroup(selectId,optGroupString)
{
var optGroup = optGroupString.split(",");
var objSelect = document.getElementsByTagName("SELECT");
var objSelectNow = objSelect[selectId];
objSelectNow.length = 1;
/// 成组添加Options
for (i=1; i<optGroup.length; i++)
{
addOption(objSelectNow, optGroup[i], i);
}
}
服务端处理程序select.server.php
<?php
Header("Content-type:text/html;charset=GBK");//加入头，防止乱码
$referUrl=$_SERVER['HTTP_REFERER'];//取得上一页面地址
$referHost=$_SERVER['HTTP_HOST'];//取得当前主机名
$referFile=explode("/",$referUrl);//取得上一前面的主机名$referFile[2]
if($referFile[2]!=$referHost)//如果上一页面与本服务端程序不在同一主机则禁止执行
{
exit();
}
$aryTree = file("china.txt");//加载数据文件
foreach($aryTree as $key=>$value)
{
$province[$key]=explode(",",trim($value));
$city[$key]=trim($value);
}
$action=$_GET["action"];
if($action=="province"||$action=="")
{//action为province时进行以下操作，输出省
$provinceStr="";
for($i=0;$i<count($province);++$i)
{
$provinceStr.=$province[$i][0].",";
}
$pattern=",$";
$provinceStr=ereg_replace($pattern,"",$provinceStr);
echo $provinceStr;
}else if($action=="city"){//否则为province时输出市
$id=$_GET["id"];
echo $city[$id];
}else if($action=="district"){//否则为district，输出省市
$id=$_GET["id"];
$id1=$_GET["id1"];
echo $province[$id][0].$province[$id][$id1];
}else{//否则报错
echo "程序出错";
exit();
}
?>
前台显示页面demo.htm
<!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>ajax无刷新二级联动下拉菜单(省市联动)演示V1.0</title>
</head>
<script language="javascript" src="js/ajax.js">//
