// =================================================================== // Author: Matt Kruse // WWW: http://www.AjaxToolbox.com/ // =================================================================== /** * The AjaxRequest class is a wrapper for the XMLHttpRequest objects which * are available in most modern browsers. It simplifies the interfaces for * making Ajax requests, adds commonly-used convenience methods, and makes * the process of handling state changes more intuitive. * An object may be instantiated and used, or the Class methods may be used * which internally create an AjaxRequest object. */ function AjaxRequest() { var req = new Object(); // ------------------- // Instance properties // ------------------- /** * Timeout period (in ms) until an async request will be aborted, and * the onTimeout function will be called */ req.timeout = null; /** * Since some browsers cache GET requests via XMLHttpRequest, an * additional parameter called AjaxRequestUniqueId will be added to * the request URI with a unique numeric value appended so that the requested * URL will not be cached. */ req.generateUniqueUrl = true; /** * The url that the request will be made to, which defaults to the current * url of the window */ req.url = window.location.href; /** * The method of the request, either GET (default), POST, or HEAD */ req.method = "GET"; /** * Whether or not the request will be asynchronous. In general, synchronous * requests should not be used so this should rarely be changed from true */ req.async = true; /** * The username used to access the URL */ req.username = null; /** * The password used to access the URL */ req.password = null; /** * The parameters is an object holding name/value pairs which will be * added to the url for a GET request or the request content for a POST request */ req.parameters = new Object(); /** * The sequential index number of this request, updated internally */ req.requestIndex = AjaxRequest.numAjaxRequests++; /** * Indicates whether a response has been received yet from the server */ req.responseReceived = false; /** * The name of the group that this request belongs to, for activity * monitoring purposes */ req.groupName = null; /** * The query string to be added to the end of a GET request, in proper * URIEncoded format */ req.queryString = ""; /** * After a response has been received, this will hold the text contents of * the response - even in case of error */ req.responseText = null; /** * After a response has been received, this will hold the XML content */ req.responseXML = null; /** * After a response has been received, this will hold the status code of * the response as returned by the server. */ req.status = null; /** * After a response has been received, this will hold the text description * of the response code */ req.statusText = null; /** * An internal flag to indicate whether the request has been aborted */ req.aborted = false; /** * The XMLHttpRequest object used internally */ req.xmlHttpRequest = null; // -------------- // Event handlers // -------------- /** * If a timeout period is set, and it is reached before a response is * received, a function reference assigned to onTimeout will be called */ req.onTimeout = null; /** * A function reference assigned will be called when readyState=1 */ req.onLoading = null; /** * A function reference assigned will be called when readyState=2 */ req.onLoaded = null; /** * A function reference assigned will be called when readyState=3 */ req.onInteractive = null; /** * A function reference assigned will be called when readyState=4 */ req.onComplete = null; /** * A function reference assigned will be called after onComplete, if * the statusCode=200 */ req.onSuccess = null; /** * A function reference assigned will be called after onComplete, if * the statusCode != 200 */ req.onError = null; /** * If this request has a group name, this function reference will be called * and passed the group name if this is the first request in the group to * become active */ req.onGroupBegin = null; /** * If this request has a group name, and this request is the last request * in the group to complete, this function reference will be called */ req.onGroupEnd = null; // Get the XMLHttpRequest object itself req.xmlHttpRequest = AjaxRequest.getXmlHttpRequest(); if (req.xmlHttpRequest==null) { return null; } // ------------------------------------------------------- // Attach the event handlers for the XMLHttpRequest object // ------------------------------------------------------- req.xmlHttpRequest.onreadystatechange = function() { if (req==null || req.xmlHttpRequest==null) { return; } if (req.xmlHttpRequest.readyState==1) { req.onLoadingInternal(req); } if (req.xmlHttpRequest.readyState==2) { req.onLoadedInternal(req); } if (req.xmlHttpRequest.readyState==3) { req.onInteractiveInternal(req); } if (req.xmlHttpRequest.readyState==4) { req.onCompleteInternal(req); } }; // --------------------------------------------------------------------------- // Internal event handlers that fire, and in turn fire the user event handlers // --------------------------------------------------------------------------- // Flags to keep track if each event has been handled, in case of // multiple calls (some browsers may call the onreadystatechange // multiple times for the same state) req.onLoadingInternalHandled = false; req.onLoadedInternalHandled = false; req.onInteractiveInternalHandled = false; req.onCompleteInternalHandled = false; req.onLoadingInternal = function() { if (req.onLoadingInternalHandled) { return; } AjaxRequest.numActiveAjaxRequests++; if (AjaxRequest.numActiveAjaxRequests==1 && typeof(window['AjaxRequestBegin'])=="function") { AjaxRequestBegin(); } if (req.groupName!=null) { if (typeof(AjaxRequest.numActiveAjaxGroupRequests[req.groupName])=="undefined") { AjaxRequest.numActiveAjaxGroupRequests[req.groupName] = 0; } AjaxRequest.numActiveAjaxGroupRequests[req.groupName]++; if (AjaxRequest.numActiveAjaxGroupRequests[req.groupName]==1 && typeof(req.onGroupBegin)=="function") { req.onGroupBegin(req.groupName); } } if (typeof(req.onLoading)=="function") { req.onLoading(req); } req.onLoadingInternalHandled = true; }; req.onLoadedInternal = function() { if (req.onLoadedInternalHandled) { return; } if (typeof(req.onLoaded)=="function") { req.onLoaded(req); } req.onLoadedInternalHandled = true; }; req.onInteractiveInternal = function() { if (req.onInteractiveInternalHandled) { return; } if (typeof(req.onInteractive)=="function") { req.onInteractive(req); } req.onInteractiveInternalHandled = true; }; req.onCompleteInternal = function() { if (req.onCompleteInternalHandled || req.aborted) { return; } req.onCompleteInternalHandled = true; AjaxRequest.numActiveAjaxRequests--; if (AjaxRequest.numActiveAjaxRequests==0 && typeof(window['AjaxRequestEnd'])=="function") { AjaxRequestEnd(req.groupName); } if (req.groupName!=null) { AjaxRequest.numActiveAjaxGroupRequests[req.groupName]--; if (AjaxRequest.numActiveAjaxGroupRequests[req.groupName]==0 && typeof(req.onGroupEnd)=="function") { req.onGroupEnd(req.groupName); } } req.responseReceived = true; req.status = req.xmlHttpRequest.status; req.statusText = req.xmlHttpRequest.statusText; req.responseText = req.xmlHttpRequest.responseText; req.responseXML = req.xmlHttpRequest.responseXML; if (typeof(req.onComplete)=="function") { req.onComplete(req); } if (req.xmlHttpRequest.status==200 && typeof(req.onSuccess)=="function") { req.onSuccess(req); } else if (typeof(req.onError)=="function") { req.onError(req); } // Clean up so IE doesn't leak memory delete req.xmlHttpRequest['onreadystatechange']; req.xmlHttpRequest = null; }; req.onTimeoutInternal = function() { if (req!=null && req.xmlHttpRequest!=null && !req.onCompleteInternalHandled) { req.aborted = true; req.xmlHttpRequest.abort(); AjaxRequest.numActiveAjaxRequests--; if (AjaxRequest.numActiveAjaxRequests==0 && typeof(window['AjaxRequestEnd'])=="function") { AjaxRequestEnd(req.groupName); } if (req.groupName!=null) { AjaxRequest.numActiveAjaxGroupRequests[req.groupName]--; if (AjaxRequest.numActiveAjaxGroupRequests[req.groupName]==0 && typeof(req.onGroupEnd)=="function") { req.onGroupEnd(req.groupName); } } if (typeof(req.onTimeout)=="function") { req.onTimeout(req); } // Opera won't fire onreadystatechange after abort, but other browsers do. // So we can't rely on the onreadystate function getting called. Clean up here! delete req.xmlHttpRequest['onreadystatechange']; req.xmlHttpRequest = null; } }; // ---------------- // Instance methods // ---------------- /** * The process method is called to actually make the request. It builds the * querystring for GET requests (the content for POST requests), sets the * appropriate headers if necessary, and calls the * XMLHttpRequest.send() method */ req.process = function() { if (req.xmlHttpRequest!=null) { // Some logic to get the real request URL if (req.generateUniqueUrl && req.method=="GET") { req.parameters["AjaxRequestUniqueId"] = new Date().getTime() + "" + req.requestIndex; } var content = null; // For POST requests, to hold query string for (var i in req.parameters) { if (req.queryString.length>0) { req.queryString += "&"; } req.queryString += encodeURIComponent(i) + "=" + encodeURIComponent(req.parameters[i]); } if (req.method=="GET") { if (req.queryString.length>0) { req.url += ((req.url.indexOf("?")>-1)?"&":"?") + req.queryString; } } req.xmlHttpRequest.open(req.method,req.url,req.async,req.username,req.password); if (req.method=="POST") { if (typeof(req.xmlHttpRequest.setRequestHeader)!="undefined") { req.xmlHttpRequest.setRequestHeader('Content-type', 'application/x-www-form-urlencoded'); } content = req.queryString; } if (req.timeout>0) { setTimeout(req.onTimeoutInternal,req.timeout); } req.xmlHttpRequest.send(content); } }; /** * An internal function to handle an Object argument, which may contain * either AjaxRequest field values or parameter name/values */ req.handleArguments = function(args) { for (var i in args) { // If the AjaxRequest object doesn't have a property which was passed, treat it as a url parameter if (typeof(req[i])=="undefined") { req.parameters[i] = args[i]; } else { req[i] = args[i]; } } }; /** * Returns the results of XMLHttpRequest.getAllResponseHeaders(). * Only available after a response has been returned */ req.getAllResponseHeaders = function() { if (req.xmlHttpRequest!=null) { if (req.responseReceived) { return req.xmlHttpRequest.getAllResponseHeaders(); } alert("Cannot getAllResponseHeaders because a response has not yet been received"); } }; /** * Returns the the value of a response header as returned by * XMLHttpRequest,getResponseHeader(). * Only available after a response has been returned */ req.getResponseHeader = function(headerName) { if (req.xmlHttpRequest!=null) { if (req.responseReceived) { return req.xmlHttpRequest.getResponseHeader(headerName); } alert("Cannot getResponseHeader because a response has not yet been received"); } }; return req; } // --------------------------------------- // Static methods of the AjaxRequest class // --------------------------------------- /** * Returns an XMLHttpRequest object, either as a core object or an ActiveX * implementation. If an object cannot be instantiated, it will return null; */ AjaxRequest.getXmlHttpRequest = function() { if (window.XMLHttpRequest) { return new XMLHttpRequest(); } else if (window.ActiveXObject) { // Based on http://jibbering.com/2002/4/httprequest.html /*@cc_on @*/ /*@if (@_jscript_version >= 5) try { return new ActiveXObject("Msxml2.XMLHTTP"); } catch (e) { try { return new ActiveXObject("Microsoft.XMLHTTP"); } catch (E) { return null; } } @end @*/ } else { return null; } }; /** * See if any request is active in the background */ AjaxRequest.isActive = function() { return (AjaxRequest.numActiveAjaxRequests>0); }; /** * Make a GET request. Pass an object containing parameters and arguments as * the second argument. * These areguments may be either AjaxRequest properties to set on the request * object or name/values to set in the request querystring. */ AjaxRequest.get = function(args) { AjaxRequest.doRequest("GET",args); }; /** * Make a POST request. Pass an object containing parameters and arguments as * the second argument. * These areguments may be either AjaxRequest properties to set on the request * object or name/values to set in the request querystring. */ AjaxRequest.post = function(args) { AjaxRequest.doRequest("POST",args); }; /** * The internal method used by the .get() and .post() methods */ AjaxRequest.doRequest = function(method,args) { if (typeof(args)!="undefined" && args!=null) { var myRequest = new AjaxRequest(); myRequest.method = method; myRequest.handleArguments(args); myRequest.process(); } } ; /** * Submit a form. The requested URL will be the form's ACTION, and the request * method will be the form's METHOD. * Returns true if the submittal was handled successfully, else false so it * can easily be used with an onSubmit event for a form, and fallback to * submitting the form normally. */ AjaxRequest.submit = function(theform, args) { var myRequest = new AjaxRequest(); if (myRequest==null) { return false; } var serializedForm = AjaxRequest.serializeForm(theform); myRequest.method = theform.method.toUpperCase(); myRequest.url = theform.action; myRequest.handleArguments(args); myRequest.queryString = serializedForm; myRequest.process(); return true; }; /** * Serialize a form into a format which can be sent as a GET string or a POST * content.It correctly ignores disabled fields, maintains order of the fields * as in the elements[] array. The 'file' input type is not supported, as * its content is not available to javascript. This method is used internally * by the submit class method. */ AjaxRequest.serializeForm = function(theform) { var els = theform.elements; var len = els.length; var queryString = ""; this.addField = function(name,value) { if (queryString.length>0) { queryString += "&"; } queryString += encodeURIComponent(name) + "=" + encodeURIComponent(value); }; for (var i=0; i=0) { this.addField(el.name,el.options[el.selectedIndex].value); } break; case 'select-multiple': for (var j=0; j