1  
   2  //+ Jonas Raoni Soares Silva
   3  //@ http://jsfromhell.com/classes/http-request [v1.0]
   4  
   5  HTTPRequest = function(){};
   6  with({$: HTTPRequest.prototype}){
   7  	$.isSupported = function(){
   8  		return !!this.getConnection();
   9  	};
  10  	$.events = ["start", "open", "send", "load", "end"];
  11  	$.filter = encodeURIComponent;
  12  	$.getConnection = function(){
  13  		var i, o = [function(){return new ActiveXObject("Msxml2.XMLHTTP");},
  14  		function(){return new ActiveXObject("Microsoft.XMLHTTP");},
  15  		function(){return new XMLHttpRequest;}];
  16  		for(i = o.length; i--;) try{return o[i]();} catch(e){}
  17  		return null;
  18  	};
  19  	$.formatParams = function(params){
  20  		var i, r = [];
  21  		for(i in params) r[r.length] = i + "=" + (this.filter ? this.filter(params[i]) : params[i]);
  22  		return r.join("&");
  23  	};
  24  	$.get = function(url, params, handler, waitResponse){
  25  		return this.request("GET", url + (url.indexOf("?") + 1 ? "&" : "?") + this.formatParams(params), null, handler, null, waitResponse);
  26  	};
  27  	$.post = function(url, params, handler, waitResponse){
  28  		return this.request("POST", url, params = this.formatParams(params), handler, {
  29  			"Connection": "close",
  30  			"Content-Length": params.length,
  31  			"Method": "POST " + url + " HTTP/1.1",
  32  			"Content-Type": "application/x-www-form-urlencoded; charset=utf-8"
  33  		}, waitResponse);
  34  	};
  35  	$.request = function(method, url, params, handler, headers, waitResponse){
  36  		var i, o = this.getConnection(), f = handler instanceof Function;
  37  		try{
  38  			o.open(method, url, !waitResponse);
  39  			waitResponse || (o.onreadystatechange = function(){
  40  				var s = $.events[o.readyState];
  41  				f ? handler(o) : s in handler && handler[s](o);
  42  			});
  43  			o.setRequestHeader("HTTP_USER_AGENT", "XMLHttpRequest");
  44  			for(i in headers)
  45  				o.setRequestHeader(i, headers[i]);
  46  			o.send(params);
  47  			waitResponse && (f ? handler(o) : handler["end"] && handler["end"](o));
  48  			return true;
  49  		}
  50  		catch(e){
  51  			return false;
  52  		}
  53  	};
  54  }

   1  
   2  <fieldset>
   3  	<legend>HTTPRequest example</legend>
   4  	<input type="button" value="POST request with generic listener and params passage" onclick="genericHandler()" />
   5  	<br /><input type="button" value="GET request with specific listener (binded on load and end)" onclick="specificHandler()" />
   6  
   7  <script type="text/javascript">
   8  //<![CDATA[
   9  
  10  var r = new HTTPRequest;
  11  
  12  function myHandler(o){
  13  	alert("Current event = " + r.events[o.readyState] +
  14  	"\nAvailable \"responseText.length\" = " + o.responseText.length);
  15  }
  16  function genericHandler(){
  17  	r.post(location.href, {param: "abcde", name: "Jonas", site: "http://jsfromhell.com"}, myHandler);
  18  }
  19  function specificHandler(){
  20  	r.get(location.href, null, {"load": myHandler, "end": myHandler});
  21  }
  22  document.write(
  23  	"<br />Supports XMLHTTPRequest = ".bold() + r.isSupported(),
  24  	"<br />Encoded with the default filter (\"encodeURIComponent\") = ".bold() + r.formatParams({nameA: "aeiou", nameB: "áéíóú"})
  25  );
  26  
  27  r.filter = escape;
  28  document.write("<br />Encoded with \"escape\" filter = ".bold() + r.formatParams({nameA: "aeiou", nameB: "áéíóú"}));
  29  
  30  r.filter = null;
  31  document.write("<br />Encoded with no filtering = ".bold() + r.formatParams({nameA: "aeiou", nameB: "áéíóú"}));
  32  
  33  //]]>
  34  </script>
  35  </fieldset>