求javascript高手帮忙，解释一段天气预报的代码，最好是每一句的意思

显示全部楼层 · 2011-6-26 04:10:40

varWeaherDataList;
varxhr;
functioninit(){
choose();
}//初始化变量
functiongetData(cityName){
xhr=newXMLHttpRequest();
varurl=\"<ahref=\"http://www.polyvi.com.cn:8090/weather/servlet/cityservice?city=\"target=\"_blank\">http://www.polyvi.com.cn:8090/weather/servlet/cityservice?city=</a>\";//后台服务器地址
url=cityName;
xhr.open(\"GET\",url,true);
xhr.onreadystatechange=forCallback;
xhr.send(null);
}//联网获取服务器数据
functionforCallback(){
if(xhr.readyState==4||xhr.readyState==\"complete\"){
varstring=xhr.responseText;
if(string==\"0\"){
alert(\"查询失败。。。\");
return;
}else{
//WeaherDataList=string;
eval(\"WeaherDataList\"\"=\"string);
fillData();
return;
}
}
}//获取数据异步回调函数
functionfillData(){
window.prepareForTransition();
$(\"cityname\").firstChild.data=WeaherDataList.city;
$(\"thermometer\").firstChild.data=WeaherDataList.temperature;
$(\"weather\").firstChild.data=WeaherDataList.description;
$(\"logo\").src=\"img/\"WeaherDataList.wcode\".png\";
window.performTransition();
}//显示查询结果的数据

functionfillNoData(){
window.prepareForTransition();
$(\"city\").firstChild.data=cityName;
$(\"thermometer\").firstChild.data=\"failed\";
$(\"weather\").firstChild.data=\"查询失败\";
window.performTransition();
}

functionchoose(){
window.prepareForTransition();
$(\"showBar\").style.display=\"none\";
$(\"chooseBar\").style.display=\"block\";
window.document.body.focus();
window.performTransition();
}

functionsubmit(){
window.prepareForTransition();
$(\"chooseBar\").style.display=\"none\";
$(\"showBar\").style.display=\"block\";
window.document.body.focus();
varcityName=$(\"cityName\").value;
$(\"city\").firstChild.data=\"请等待\";
$(\"thermometer\").firstChild.data=\"查询中\";
$(\"weather\").firstChild.data=\"查询中\";
window.performTransition();
getData(cityName);
}//发起查询的请求

function$(id){
returndocument.getElementById(id);
}//通过id获取dom对象

千问 · 2011-6-26 04:10:40

varWeaherDataList;
varxhr;
functioninit(){
choose();//调用函数开头
}//初始化变量
functiongetData(cityName){
xhr=newXMLHttpRequest();
varurl=\"<ahref=\"http://www.polyvi.com.cn:8090/weather/servlet/cityservice?city=\"target=\"_blank\">http://www.polyvi.com.cn:8090/weather/servlet/cityservice?city=</a>\";//后台服务器地址
url=cityName;
xhr.open(\"GET\",url,true);
xhr.onreadystatechange=forCallback;
xhr.send(null);//从服务器取得正确信息，得到时间等
}//联网获取服务器数据
functionforCallback(){
if(xhr.readyState==4||xhr.readyState==\"complete\"){
varstring=xhr.responseText;
if(string==\"0\"){
alert(\"查询失败。。。\");
return;//发生非法请求或则服务器维护时出现错误，不能从服务器取得信息。
}else{
//WeaherDataList=string;
eval(\"WeaherDataList\"\"=\"string);//获取天气列表数据
fillData();
return;//返回
}
}
}//获取数据异步回调函数
functionfillData(){
window.prepareForTransition();
$(\"cityname\").firstChild.data=WeaherDataList.city;
$(\"thermometer\").firstChild.data=WeaherDataList.temperature;
$(\"weather\").firstChild.data=WeaherDataList.description;
$(\"logo\").src=\"img/\"WeaherDataList.wcode\".png\";
window.performTransition();
}//与服务器对接，获得数据，操作合法给予查看，请求成功

functionfillNoData(){
window.prepareForTransition();
$(\"city\").firstChild.data=cityName;
$(\"thermometer\").firstChild.data=\"failed\";
$(\"weather\").firstChild.data=\"查询失败\";
window.performTransition();
}//服务器响应超时，导致失败，给予弹窗“查询失败”

functionchoose(){
window.prepareForTransition();
$(\"showBar\").style.display=\"none\";
$(\"chooseBar\").style.display=\"block\";
window.document.body.focus();
window.performTransition();
}//调用本地函数进行翻译

functionsubmit(){
window.prepareForTransition();
$(\"chooseBar\").style.display=\"none\";
$(\"showBar\").style.display=\"block\";
window.document.body.focus();
varcityName=$(\"cityName\").value;
$(\"city\").firstChild.data=\"请等待\";
$(\"thermometer\").firstChild.data=\"查询中\";
$(\"weather\").firstChild.data=\"查询中\";
window.performTransition();
getData(cityName);
}//发起查询的请求

function$(id){
returndocument.getElementById(id);
}//通过id获取dom对象，就是对信息的取回结束，ok
睬我阿、！！！！！不懂QQ：767999058

千问 · 2011-6-26 04:10:40

这个我主要是想搞懂每句代码的意思，答辩的时候怕被问到，我不懂，大哥你要懂请帮忙一下