<html>
<head>
<base href="<%=basePath%>">
<title>this is a test for using XML to understand the way how to use AJAX</title>
<script type="text/javascript">
var xmlHttp;
var requestType = "";
function createXMLHttpRequest() {
if(window.ActiveXObject) {
xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
}
else if(window.XMLHttpRequest) {
xmlHttp = new XMLHttpRequest();
}
}
function startRequest(requestList) {
requestType = requestList;
createXMLHttpRequest();
xmlHttp.onreadystatechange = handleStateChange;
xmlHttp.open("GET","parseXML.xml",true);
xmlHttp.send(null);
}
function handleStateChange() {
if(xmlHttp.readyState == 4) {
if(xmlHttp.status == 200) {
if(requestType == "north") {
listNorthStates();
}
else if(requestType == "all") {
listAllStates();
}
)
)
}
function listNorthStates() {
var xmlDoc = xmlHttp.responseXML;
var northNode = xmlDoc.getElementsByTagName("north")[0];
var out = "northern states";
var northStates = northNode.getElementsByTagName("state");
outputList(out, northStates);
}
function listAllStates() {
var xmlDoc = xmlHttp.responseXML;
var allStates = xmlDoc.getElementsByTagName("state");
outputList("All State In Document", allStates);
}
function outputList(title, states) {
var out = title;
var currentState = null;
for(var i = 0; i < states.length; i++) {
currentState = states[i];
out = out + "\n- " +currentState.childNodes[0].nodeValue;
}
alert(out);
}
</script>
</head>
<body>
<h1>Process XML Document of U.S States </h1>
<br/><br/>
<form action="#">
<input type="button" value="view all listed states" onclick="startRequest('all');" />
<br/><br/>
<input type="button" value="view all listed northern states" onclick="startRequest('north');" />
</form>
</body>
</html>
这段代码在运行的时候总是在下面两个<input>处报错：缺少对象！用alert函数测试了，居然无法弹出对话框！请各位帮个忙！
