ajax手记

封装了一个ajax简易js.
ajax.js:

function action(url)
{
createRequest();
request.open("GET", url, true);
request.onreadystatechange = updatePage;
request.send(null);
}

function createRequest() {
try {
request = new XMLHttpRequest();
} catch (trymicrosoft) {
try {
request = new ActiveXObject("Msxml2.XMLHTTP");
} catch (othermicrosoft) {
try {
request = new ActiveXObject("Microsoft.XMLHTTP");
} catch (failed) {
request = false;
}
}
}
if (!request)
alert("Error initializing XMLHttpRequest!");
}

function updatePage()
{
if (request.readyState == 4)
{
if (request.status == 200)
{
actionok(request.responseText);
//alert("Server is done!"+ request.responseText);
}
else if (request.status == 404)
{
alert("Request URL does not exist");
}
else
alert("Error: status code is " + request.status);
}

}


使用：