本文實例講述了jsp實現將信息放入xml中的方法。分享給大家供大家參考,具體如下:
一、jsp代碼:
省: <select id="province" name="province" onchange="jsSubmit()">
<option value="北京" selected="selected">北京</option>
<option value="廣東">廣東</option>
<option value="海南">海南</option>
</select>
市: <select id="city" name="city">
<option value="北京">北京</option>
</select>
二、ajax代碼創建服務器請求代碼不用寫了,寫onchange時候的事件jsSubmit吧:
function jsSubmit() {
createXMLHttpRequest();
var province = document.getElementById("province");
//解決客戶端向服務器端傳輸中文亂碼
var uri = "AjaxAction?value=" + encodeURI(encodeURI(province.value));
xmlHttp.open("POST", uri, true);
xmlHttp.setRequestHeader("Content-Type","application/x-www-form-urlencoded;")
xmlHttp.onreadystatechange = processResponse;//回調函數啊!
xmlHttp.send(null);
}
三、servlet
public class AjaxAction extends HttpServlet {
private static final long serialVersionUID = 1L;
private static Map<String, String[]> map = new HashMap<String, String[]>();
static {
String[] cities1 = { "海口", "瓊海", "三亞" };
String[] cities2 = { "廣州", "珠海", "佛山", "深圳" };
String[] cities3 = { "北京" };
map.put("北京", cities3);
map.put("廣東", cities2);
map.put("海南", cities1);
}
st方法{
String province = request.getParameter("value");// 解決客戶端向服務器端傳輸中文亂碼
String proviceCN = URLDecoder.decode(province, "UTF-8");
String[] cities = map.get(proviceCN);//根據傳來的省,查出已經存放進map中對應的市
response.setContentType("text/xml; charset=UTF-8");
StringBuffer buff=new StringBuffer("<citylist>");///准備拼字符串......
for (String city : cities)
{
buff.append("<city>").append(city) .append("</city>");
}
buff.append("</citylist>");
response.getWriter().println(buff.toString());
四、ajax的回調函數
function processResponse() {
if(xmlHttp.readyState == 4) {
if(xmlHttp.status == 200) {
var cities = xmlHttp.responseXML.getElementsByTagName("city");
var displaySelect = document.getElementById("city");
displaySelect.innerHTML = null;
for (var i= 0 ;i < cities.length ; i++){
if (i == 0) {
var a= xmlHttp.responseXML.getElementsByTagName("city")[i].firstChild.data;//用firstChild方法,其他方法我用text方法不管用~不知道怎麼回事
var op = new Option(a, a, true, true);
} else {
var a= xmlHttp.responseXML.getElementsByTagName("city")[i].firstChild.data;
var op = new Option(a, a);
alert(a);
}
displaySelect.options[i] = op;
}
} else {
window.alert("請求的頁面有異常");
}
}
}
希望本文所述對大家jsp程序設計有所幫助。