Class to make remote requests, which can be used on the popular "AJAX".
[UPDATED CODE AND HELP CAN BE FOUND HERE]
//+ Jonas Raoni Soares Silva
//@ http://jsfromhell.com/classes/http-request [v1.0]
HTTPRequest = function(){};
with({$: HTTPRequest.prototype}){
$.isSupported = function(){
return !!this.getConnection();
};
$.events = ["start", "open", "send", "load", "end"];
$.filter = encodeURIComponent;
$.getConnection = function(){
var i, o = [function(){return new ActiveXObject("Msxml2.XMLHTTP");},
function(){return new ActiveXObject("Microsoft.XMLHTTP");},
function(){return new XMLHttpRequest;}];
for(i = o.length; i--;) try{return o[i]();} catch(e){}
return null;
};
$.formatParams = function(params){
var i, r = [];
for(i in params) r[r.length] = i + "=" + (this.filter ? this.filter(params[i]) : params[i]);
return r.join("&");
};
$.get = function(url, params, handler, waitResponse){
return this.request("GET", url + (url.indexOf("?") + 1 ? "&" : "?") + this.formatParams(params), null, handler, null, waitResponse);
};
$.post = function(url, params, handler, waitResponse){
return this.request("POST", url, params = this.formatParams(params), handler, {
"Connection": "close",
"Content-Length": params.length,
"Method": "POST " + url + " HTTP/1.1",
"Content-Type": "application/x-www-form-urlencoded; charset=utf-8"
}, waitResponse);
};
$.request = function(method, url, params, handler, headers, waitResponse){
var i, o = this.getConnection(), f = handler instanceof Function;
try{
o.open(method, url, !waitResponse);
waitResponse || (o.onreadystatechange = function(){
var s = $.events[o.readyState];
f ? handler(o) : s in handler && handler[s](o);
});
o.setRequestHeader("HTTP_USER_AGENT", "XMLHttpRequest");
for(i in headers)
o.setRequestHeader(i, headers[i]);
o.send(params);
waitResponse && (f ? handler(o) : handler["end"] && handler["end"](o));
return true;
}
catch(e){
return false;
}
};
}
Example
<fieldset>
<legend>HTTPRequest example</legend>
<input type="button" value="POST request with generic listener and params passage" onclick="genericHandler()" />
<br /><input type="button" value="GET request with specific listener (binded on load and end)" onclick="specificHandler()" />
<script type="text/javascript">
//<![CDATA[
var r = new HTTPRequest;
function myHandler(o){
alert("Current event = " + r.events[o.readyState] +
"\nAvailable \"responseText.length\" = " + o.responseText.length);
}
function genericHandler(){
r.post(location.href, {param: "abcde", name: "Jonas", site: "http://jsfromhell.com"}, myHandler);
}
function specificHandler(){
r.get(location.href, null, {"load": myHandler, "end": myHandler});
}
document.write(
"<br />Supports XMLHTTPRequest = ".bold() + r.isSupported(),
"<br />Encoded with the default filter (\"encodeURIComponent\") = ".bold() + r.formatParams({nameA: "aeiou", nameB: "áéíóú"})
);
r.filter = escape;
document.write("<br />Encoded with \"escape\" filter = ".bold() + r.formatParams({nameA: "aeiou", nameB: "áéíóú"}));
r.filter = null;
document.write("<br />Encoded with no filtering = ".bold() + r.formatParams({nameA: "aeiou", nameB: "áéíóú"}));
//]]>
</script>
</fieldset>
