Removed re-usability from jXHR object (no more open, send & onreadystatechange suppor...
[jquery.git] / src / ajax.js
1 (function( jQuery ) {
2         
3 var r20 = /%20/g,
4         rbracket = /\[\]$/,
5         rhash = /#.*$/,
6         rheaders = /^(.*?):\s*(.*?)\r?$/mg, // IE leaves an \r character at EOL
7         rinput = /^(?:color|date|datetime|email|hidden|month|number|password|range|search|tel|text|time|url|week)$/i,
8         rnoContent = /^(?:GET|HEAD)$/,
9         rquery = /\?/,
10         rscript = /<script\b[^<]*(?:(?!<\/script>)<[^<]*)*<\/script>/gi,
11         rselectTextarea = /^(?:select|textarea)/i,
12         rts = /([?&])_=[^&]*/,
13         rurl = /^(\w+:)?\/\/([^\/?#]+)/,
14
15         // Slice function
16         sliceFunc = Array.prototype.slice,
17         
18         // Keep a copy of the old load method
19         _load = jQuery.fn.load;
20
21 jQuery.fn.extend({
22         load: function( url, params, callback ) {
23                 if ( typeof url !== "string" && _load ) {
24                         return _load.apply( this, arguments );
25
26                 // Don't do a request if no elements are being requested
27                 } else if ( !this.length ) {
28                         return this;
29                 }
30
31                 var off = url.indexOf(" ");
32                 if ( off >= 0 ) {
33                         var selector = url.slice(off, url.length);
34                         url = url.slice(0, off);
35                 }
36
37                 // Default to a GET request
38                 var type = "GET";
39
40                 // If the second parameter was provided
41                 if ( params ) {
42                         // If it's a function
43                         if ( jQuery.isFunction( params ) ) {
44                                 // We assume that it's the callback
45                                 callback = params;
46                                 params = null;
47
48                         // Otherwise, build a param string
49                         } else if ( typeof params === "object" ) {
50                                 params = jQuery.param( params, jQuery.ajaxSettings.traditional );
51                                 type = "POST";
52                         }
53                 }
54
55                 var self = this;
56
57                 // Request the remote document
58                 jQuery.ajax({
59                         url: url,
60                         type: type,
61                         dataType: "html",
62                         data: params,
63                         complete: function( res, status ) {
64                                 // If successful, inject the HTML into all the matched elements
65                                 if ( status === "success" || status === "notmodified" ) {
66                                         // See if a selector was specified
67                                         self.html( selector ?
68                                                 // Create a dummy div to hold the results
69                                                 jQuery("<div>")
70                                                         // inject the contents of the document in, removing the scripts
71                                                         // to avoid any 'Permission Denied' errors in IE
72                                                         .append(res.responseText.replace(rscript, ""))
73
74                                                         // Locate the specified elements
75                                                         .find(selector) :
76
77                                                 // If not, just inject the full result
78                                                 res.responseText );
79                                 }
80
81                                 if ( callback ) {
82                                         self.each( callback, [res.responseText, status, res] );
83                                 }
84                         }
85                 });
86
87                 return this;
88         },
89
90         serialize: function() {
91                 return jQuery.param(this.serializeArray());
92         },
93
94         serializeArray: function() {
95                 return this.map(function(){
96                         return this.elements ? jQuery.makeArray(this.elements) : this;
97                 })
98                 .filter(function(){
99                         return this.name && !this.disabled &&
100                                 (this.checked || rselectTextarea.test(this.nodeName) ||
101                                         rinput.test(this.type));
102                 })
103                 .map(function(i, elem){
104                         var val = jQuery(this).val();
105
106                         return val == null ?
107                                 null :
108                                 jQuery.isArray(val) ?
109                                         jQuery.map( val, function(val, i){
110                                                 return {name: elem.name, value: val};
111                                         }) :
112                                         {name: elem.name, value: val};
113                 }).get();
114         }
115 });
116
117 // Attach a bunch of functions for handling common AJAX events
118 jQuery.each( "ajaxStart ajaxStop ajaxComplete ajaxError ajaxSuccess ajaxSend".split(" "), function(i,o){
119         jQuery.fn[o] = function(f){
120                 return this.bind(o, f);
121         };
122 });
123
124 jQuery.each( [ "get", "post" ], function( i, method ) {
125         jQuery[ method ] = function( url, data, callback, type ) {
126                 // shift arguments if data argument was omited
127                 if ( jQuery.isFunction( data ) ) {
128                         type = type || callback;
129                         callback = data;
130                         data = null;
131                 }
132
133                 return jQuery.ajax({
134                         type: method,
135                         url: url,
136                         data: data,
137                         success: callback,
138                         dataType: type
139                 });
140         };
141 });
142
143 jQuery.extend({
144
145         getScript: function( url, callback ) {
146                 return jQuery.get(url, null, callback, "script");
147         },
148
149         getJSON: function( url, data, callback ) {
150                 return jQuery.get(url, data, callback, "json");
151         },
152
153         ajaxSetup: function( settings ) {
154                 jQuery.extend( jQuery.ajaxSettings, settings );
155         },
156
157         ajaxSettings: {
158                 url: location.href,
159                 global: true,
160                 type: "GET",
161                 contentType: "application/x-www-form-urlencoded",
162                 processData: true,
163                 async: true,
164                 /*
165                 timeout: 0,
166                 data: null,
167                 dataType: null,
168                 dataTypes: null,
169                 username: null,
170                 password: null,
171                 cache: null,
172                 traditional: false,
173                 */
174                 xhr: function() {
175                         return new window.XMLHttpRequest();
176                 },
177
178                 accepts: {
179                         xml: "application/xml, text/xml",
180                         html: "text/html",
181                         text: "text/plain",
182                         json: "application/json, text/javascript",
183                         "*": "*/*"
184                 },
185
186                 autoDataType: {
187                         xml: /xml/,
188                         html: /html/,
189                         json: /json/
190                 },
191
192                 // Prefilters
193                 // 1) They are useful to introduce custom dataTypes (see transport/jsonp for an example)
194                 // 2) These are called:
195                 //    * BEFORE asking for a transport
196                 //    * AFTER param serialization (s.data is a string if s.processData is true)
197                 // 3) key is the dataType
198                 // 4) the catchall symbol "*" can be used
199                 // 5) execution will start with transport dataType and THEN continue down to "*" if needed
200                 prefilters: {},
201
202                 // Transports bindings
203                 // 1) key is the dataType
204                 // 2) the catchall symbol "*" can be used
205                 // 3) selection will start with transport dataType and THEN go to "*" if needed
206                 transports: {},
207
208                 // List of data converters
209                 // 1) key format is "source_type destination_type" (a single space in-between)
210                 // 2) the catchall symbol "*" can be used for source_type
211                 dataConverters: {
212
213                         // Convert anything to text
214                         "* text": window.String,
215
216                         // Text to html (true = no transformation)
217                         "text html": true,
218
219                         // Evaluate text as a json expression
220                         "text json": jQuery.parseJSON,
221
222                         // Parse text as xml
223                         "text xml": jQuery.parseXML
224                 }
225         },
226
227         // Main method
228         // (s is used internally)
229         ajax: function( url , options , s ) {
230                 
231                 // Handle varargs
232                 if ( arguments.length === 1 ) {
233                         options = url;
234                         url = options ? options.url : undefined;
235                 }
236                 
237                 // Force options to be an object
238                 options = options || {};
239                 
240                 // Get the url if provided separately
241                 options.url = url || options.url;
242                 
243                 // Create the final options object
244                 s = jQuery.extend( true , {} , jQuery.ajaxSettings , options );
245                 
246                 // We force the original context
247                 // (plain objects used as context get extended)
248                 s.context = options.context;
249                 
250                 var // jQuery lists
251                         jQuery_lastModified = jQuery.lastModified,
252                         jQuery_etag = jQuery.etag,
253                         // Callbacks contexts
254                         callbackContext = s.context || s,
255                         globalEventContext = s.context ? jQuery( s.context ) : jQuery.event,
256                         // Deferreds
257                         deferred = jQuery.Deferred(),
258                         completeDeferred = jQuery._Deferred(),
259                         // Headers (they are sent all at once)
260                         requestHeaders = {},
261                         // Response headers
262                         responseHeadersString,
263                         responseHeaders,
264                         // transport
265                         transport,
266                         // timeout handle
267                         timeoutTimer,
268                         // The jXHR state
269                         state = 0,
270                         // Loop variable
271                         i,
272                         // Fake xhr
273                         jXHR = {
274                                 
275                                 readyState: 0,
276                                 
277                                 // Caches the header
278                                 setRequestHeader: function(name,value) {
279                                         if ( state === 0 ) {
280                                                 requestHeaders[ name.toLowerCase() ] = value;
281                                         }
282                                         return this;
283                                 },
284                                 
285                                 // Raw string
286                                 getAllResponseHeaders: function() {
287                                         return state === 2 ? responseHeadersString : null;
288                                 },
289                                 
290                                 // Builds headers hashtable if needed
291                                 // (match is used internally)
292                                 getResponseHeader: function( key , match ) {
293                                         
294                                         if ( state !== 2 ) {
295                                                 return null;
296                                         }
297                                         
298                                         if ( responseHeaders === undefined ) {
299                                                 
300                                                 responseHeaders = {};
301                                                 
302                                                 if ( typeof responseHeadersString === "string" ) {
303                                                         
304                                                         while( ( match = rheaders.exec( responseHeadersString ) ) ) {
305                                                                 responseHeaders[ match[ 1 ].toLowerCase() ] = match[ 2 ];
306                                                         }
307                                                 }
308                                         }
309                                         return responseHeaders[ key.toLowerCase() ];
310                                 },
311                                 
312                                 // Cancel the request
313                                 abort: function( statusText ) {
314                                         if ( transport && state !== 2 ) {
315                                                 transport.abort( statusText || "abort" );
316                                                 done( 0 , statusText );
317                                         }
318                                         return this;
319                                 }
320                         };
321
322                 // Callback for when everything is done
323                 // It is defined here because jslint complains if it is declared
324                 // at the end of the function (which would be more logical and readable)
325                 function done( status , statusText , response , headers) {
326                         
327                         // Called once
328                         if ( state === 2 ) {
329                                 return;
330                         }
331                         
332                         // State is "done" now
333                         state = 2;
334                         
335                         // Set readyState
336                         jXHR.readyState = status ? 4 : 0;
337
338                         // Cache response headers
339                         responseHeadersString = headers || "";
340
341                         // Clear timeout if it exists
342                         if ( timeoutTimer ) {
343                                 clearTimeout(timeoutTimer);
344                         }
345                         
346                         var // Reference url
347                                 url = s.url,
348                                 // and ifModified status
349                                 ifModified = s.ifModified,
350                                 
351                                 // Is it a success?
352                                 isSuccess = 0,
353                                 // Stored success
354                                 success,
355                                 // Stored error
356                                 error = statusText;
357                         
358                         // If not timeout, force a jQuery-compliant status text
359                         if ( statusText != "timeout" ) {
360                                 statusText = ( status >= 200 && status < 300 ) ? 
361                                         "success" :
362                                         ( status === 304 ? "notmodified" : "error" );
363                         }
364                         
365                         // If successful, handle type chaining
366                         if ( statusText === "success" || statusText === "notmodified" ) {
367                                 
368                                 // Set the If-Modified-Since and/or If-None-Match header, if in ifModified mode.
369                                 if ( s.ifModified ) {
370                                         
371                                         var lastModified = jXHR.getResponseHeader("Last-Modified"),
372                                                 etag = jXHR.getResponseHeader("Etag");
373                                                 
374                                         if (lastModified) {
375                                                 jQuery_lastModified[ s.url ] = lastModified;
376                                         }
377                                         if (etag) {
378                                                 jQuery_etag[ s.url ] = etag;
379                                         }
380                                 }
381                                 
382                                 if ( s.ifModified && statusText === "notmodified" ) {
383                                         
384                                         success = null;
385                                         isSuccess = 1;
386                                         
387                                 } else {
388                                         // Chain data conversions and determine the final value
389                                         // (if an exception is thrown in the process, it'll be notified as an error)
390                                         try {
391                                                 
392                                                 var i,
393                                                         current,
394                                                         prev,
395                                                         checker,
396                                                         conv1,
397                                                         conv2,
398                                                         oneConv,
399                                                         convertion,
400                                                         dataTypes = s.dataTypes,
401                                                         dataConverters = s.dataConverters,
402                                                         responses = {
403                                                                 "xml": "XML",
404                                                                 "text": "Text"
405                                                         };
406                                                 
407                                                 for( i = 0 ; i < dataTypes.length ; i++ ) {
408                                                         
409                                                         current = dataTypes[ i ];
410                                                         
411                                                         if ( responses[ current ] ) {
412                                                                 jXHR[ "response" + responses[ current ] ] = response;
413                                                                 responses[ current ] = 0;
414                                                         }
415                                                         
416                                                         if ( i ) {
417                                                                 
418                                                                 if ( prev !== "*" && current !== "*" && prev !== current ) {
419                                                                 
420                                                                         oneConv = conv1 = 
421                                                                                 dataConverters[ ( conversion = prev + " " + current ) ] ||
422                                                                                 dataConverters[ "* " + current ];
423                                                                         
424                                                                         if ( oneConv !== true ) {
425                                                                                 
426                                                                                 if ( ! oneConv && prev !== "text" && current !== "text" ) {
427                                                                                         conv1 = dataConverters[ prev + " text" ] || dataConverters[ "* text" ];
428                                                                                         conv2 = dataConverters[ "text " + current ];
429                                                                                 }
430                                                                                 
431                                                                                 if ( oneConv || conv1 && conv2 ) {
432                                                                                         response = oneConv ? conv1( response ) : conv2( conv1( response ) );
433                                                                                 } else {
434                                                                                         throw "no " + conversion;
435                                                                                 }
436                                                                         }
437                                                                 }
438                                                         } else if ( s.dataFilter ) {
439                                                                 
440                                                                 response = s.dataFilter( response );
441                                                                 dataTypes = s.dataTypes;
442                                                         }
443                                                         
444                                                         prev = current;
445                                                 }
446                 
447                                                 // We have a real success
448                                                 success = response;
449                                                 isSuccess = 1;
450                                                 
451                                         } catch(e) {
452                                                 
453                                                 statusText = "parsererror";
454                                                 error = "" + e;
455                                                 
456                                         }
457                                 }
458                                 
459                         } else { // if not success, mark it as an error
460                                 
461                                         error = error || statusText;
462                         }
463                                 
464                         // Set data for the fake xhr object
465                         jXHR.status = status;
466                         jXHR.statusText = statusText;
467                         
468                         // Success/Error
469                         if ( isSuccess ) {
470                                 deferred.fire( callbackContext , [ success , statusText , jXHR ] );
471                         } else {
472                                 deferred.fireReject( callbackContext , [ jXHR , statusText , error ] );
473                         }
474                         
475                         if ( s.global ) {
476                                 globalEventContext.trigger( "ajax" + ( isSuccess ? "Success" : "Error" ) ,
477                                                 [ jXHR , s , isSuccess ? success : error ] );
478                         }
479                         
480                         // Complete
481                         completeDeferred.fire( callbackContext, [ jXHR , statusText ] );
482                         
483                         if ( s.global ) {
484                                 globalEventContext.trigger( "ajaxComplete" , [ jXHR , s] );
485                                 // Handle the global AJAX counter
486                                 if ( ! --jQuery.active ) {
487                                         jQuery.event.trigger( "ajaxStop" );
488                                 }
489                         }
490                 }
491                 
492                 // Attach deferreds     
493                 jXHR.success = jXHR.then = deferred.then;
494                 jXHR.error = jXHR.fail = deferred.fail;
495                 jXHR.complete = completeDeferred.then;
496
497                 // Remove hash character (#7531: and string promotion)
498                 s.url = ( "" + s.url ).replace( rhash , "" );
499                 
500                 // Uppercase the type
501                 s.type = s.type.toUpperCase();
502                 
503                 // Determine if request has content
504                 s.hasContent = ! rnoContent.test( s.type );
505                 
506                 // Extract dataTypes list
507                 s.dataTypes = jQuery.trim( s.dataType || "*" ).toLowerCase().split( /\s+/ );
508                 
509                 // Determine if a cross-domain request is in order
510                 var parts = rurl.exec( s.url.toLowerCase() ),
511                         loc = location;
512                 s.crossDomain = !!( parts && ( parts[ 1 ] && parts[ 1 ] != loc.protocol || parts[ 2 ] != loc.host ) );
513
514                 // Convert data if not already a string
515                 if ( s.data && s.processData && typeof s.data != "string" ) {
516                         s.data = jQuery.param( s.data , s.traditional );
517                 }
518
519                 // Watch for a new set of requests
520                 if ( s.global && jQuery.active++ === 0 ) {
521                         jQuery.event.trigger( "ajaxStart" );
522                 }
523                 
524                 // Get transport
525                 transport = jQuery.ajax.prefilter( s ).transport( s );
526                 
527                 // If no transport, we auto-abort
528                 if ( ! transport ) {
529                         
530                         done( 0 , "transport not found" );
531                         jXHR = false;
532                         
533                 } else {
534                         
535                         // More options handling for requests with no content
536                         if ( ! s.hasContent ) {
537                                 
538                                 // If data is available, append data to url
539                                 if ( s.data ) {
540                                         s.url += ( rquery.test( s.url ) ? "&" : "?" ) + s.data;
541                                 }
542                                                                 
543                                 // Add anti-cache in url if needed
544                                 if ( s.cache === false ) {
545                                         
546                                         var ts = jQuery.now(),
547                                                 // try replacing _= if it is there
548                                                 ret = s.url.replace( rts , "$1_=" + ts );
549                                                 
550                                         // if nothing was replaced, add timestamp to the end
551                                         s.url = ret + ( (ret == s.url ) ? ( rquery.test( s.url ) ? "&" : "?" ) + "_=" + ts : "");
552                                 }
553                         }
554                         
555                         // Set the correct header, if data is being sent
556                         if ( ( s.data && s.hasContent ) || options.contentType ) {
557                                 requestHeaders[ "content-type" ] = s.contentType;
558                         }
559                 
560                         // Set the If-Modified-Since and/or If-None-Match header, if in ifModified mode.
561                         if ( s.ifModified ) {
562                                 if ( jQuery_lastModified[ s.url ] ) { 
563                                         requestHeaders[ "if-modified-since" ] = jQuery_lastModified[ s.url ];
564                                 }
565                                 if ( jQuery_etag[ s.url ] ) {
566                                         requestHeaders[ "if-none-match" ] = jQuery_etag[ s.url ];
567                                 }
568                         }
569                 
570                         // Set the Accepts header for the server, depending on the dataType
571                         requestHeaders.accept = s.dataTypes[ 0 ] && s.accepts[ s.dataTypes[ 0 ] ] ?
572                                 s.accepts[ s.dataTypes[ 0 ] ] + ( s.dataTypes[ 0 ] !== "*" ? ", */*; q=0.01" : "" ) :
573                                 s.accepts[ "*" ];
574                                 
575                         // Check for headers option
576                         for ( i in s.headers ) {
577                                 requestHeaders[ i.toLowerCase() ] = s.headers[ i ];
578                         }
579                         
580                         // Allow custom headers/mimetypes and early abort
581                         if ( s.beforeSend && ( s.beforeSend.call( callbackContext , jXHR , s ) === false || state === 2 ) ) {
582                                         
583                                         // Abort if not done already
584                                         done( 0 , "abort" );
585                                         jXHR = false;
586                                         
587                         } else {
588                                 
589                                 // Set state as sending
590                                 state = 1;
591                                 jXHR.readyState = 1;
592                                 
593                                 // Install callbacks on deferreds
594                                 for ( i in { success:1, error:1, complete:1 } ) {
595                                         jXHR[ i ]( s[ i ] );
596                                 }
597                                 
598                                 // Send global event
599                                 if ( s.global ) {
600                                         globalEventContext.trigger( "ajaxSend" , [ jXHR , s ] );
601                                 }
602                                 
603                                 // Timeout
604                                 if ( s.async && s.timeout > 0 ) {
605                                         timeoutTimer = setTimeout(function(){
606                                                 jXHR.abort( "timeout" );
607                                         }, s.timeout);
608                                 }
609                                 
610                                 // Try to send
611                                 try {
612                                         transport.send(requestHeaders, done);
613                                 } catch (e) {
614                                         // Propagate exception as error if not done
615                                         if ( status === 1 ) {
616
617                                                 done(0, "error", "" + e);
618                                                 jXHR = false;
619                                                 
620                                         // Simply rethrow otherwise
621                                         } else {
622                                                 jQuery.error(e);
623                                         }
624                                 }
625                         }
626                 }
627                 
628                 return jXHR;
629         },
630
631         // Serialize an array of form elements or a set of
632         // key/values into a query string
633         param: function( a, traditional ) {
634                 var s = [],
635                         add = function( key, value ) {
636                                 // If value is a function, invoke it and return its value
637                                 value = jQuery.isFunction(value) ? value() : value;
638                                 s[ s.length ] = encodeURIComponent(key) + "=" + encodeURIComponent(value);
639                         };
640
641                 // Set traditional to true for jQuery <= 1.3.2 behavior.
642                 if ( traditional === undefined ) {
643                         traditional = jQuery.ajaxSettings.traditional;
644                 }
645
646                 // If an array was passed in, assume that it is an array of form elements.
647                 if ( jQuery.isArray(a) || a.jquery ) {
648                         // Serialize the form elements
649                         jQuery.each( a, function() {
650                                 add( this.name, this.value );
651                         });
652
653                 } else {
654                         // If traditional, encode the "old" way (the way 1.3.2 or older
655                         // did it), otherwise encode params recursively.
656                         for ( var prefix in a ) {
657                                 buildParams( prefix, a[prefix], traditional, add );
658                         }
659                 }
660
661                 // Return the resulting serialization
662                 return s.join("&").replace(r20, "+");
663         }
664 });
665
666 function buildParams( prefix, obj, traditional, add ) {
667         if ( jQuery.isArray(obj) && obj.length ) {
668                 // Serialize array item.
669                 jQuery.each( obj, function( i, v ) {
670                         if ( traditional || rbracket.test( prefix ) ) {
671                                 // Treat each array item as a scalar.
672                                 add( prefix, v );
673
674                         } else {
675                                 // If array item is non-scalar (array or object), encode its
676                                 // numeric index to resolve deserialization ambiguity issues.
677                                 // Note that rack (as of 1.0.0) can't currently deserialize
678                                 // nested arrays properly, and attempting to do so may cause
679                                 // a server error. Possible fixes are to modify rack's
680                                 // deserialization algorithm or to provide an option or flag
681                                 // to force array serialization to be shallow.
682                                 buildParams( prefix + "[" + ( typeof v === "object" || jQuery.isArray(v) ? i : "" ) + "]", v, traditional, add );
683                         }
684                 });
685
686         } else if ( !traditional && obj != null && typeof obj === "object" ) {
687                 // If we see an array here, it is empty and should be treated as an empty
688                 // object
689                 if ( jQuery.isArray( obj ) || jQuery.isEmptyObject( obj ) ) {
690                         add( prefix, "" );
691
692                 // Serialize object item.
693                 } else {
694                         jQuery.each( obj, function( k, v ) {
695                                 buildParams( prefix + "[" + k + "]", v, traditional, add );
696                         });
697                 }
698
699         } else {
700                 // Serialize scalar item.
701                 add( prefix, obj );
702         }
703 }
704
705 // This is still on the jQuery object... for now
706 // Want to move this to jQuery.ajax some day
707 jQuery.extend({
708
709         // Counter for holding the number of active queries
710         active: 0,
711
712         // Last-Modified header cache for next request
713         lastModified: {},
714         etag: {}
715
716 });
717
718 //Execute or select from functions in a given structure of options
719 function ajax_selectOrExecute( structure , s ) {
720
721         var dataTypes = s.dataTypes,
722                 transportDataType,
723                 list,
724                 selected,
725                 i,
726                 length,
727                 checked = {},
728                 flag,
729                 noSelect = structure !== "transports";
730                 
731         function initSearch( dataType ) {
732
733                 flag = transportDataType !== dataType && ! checked[ dataType ];
734                 
735                 if ( flag ) {
736                         
737                         checked[ dataType ] = 1;
738                         transportDataType = dataType;
739                         list = s[ structure ][ dataType ];
740                         i = -1;
741                         length = list ? list.length : 0 ;
742                 }
743
744                 return flag;
745         }
746         
747         initSearch( dataTypes[ 0 ] );
748
749         for ( i = 0 ; ( noSelect || ! selected ) && i <= length ; i++ ) {
750                 
751                 if ( i === length ) {
752                         
753                         initSearch( "*" );
754                         
755                 } else {
756
757                         selected = list[ i ]( s , determineDataType );
758
759                         // If we got redirected to another dataType
760                         // Search there (if not in progress or already tried)
761                         if ( typeof( selected ) === "string" &&
762                                 initSearch( selected ) ) {
763
764                                 dataTypes.unshift( selected );
765                                 selected = 0;
766                         }
767                 }
768         }
769
770         return noSelect ? jQuery.ajax : selected;
771 }
772
773 // Add an element to one of the structures in ajaxSettings
774 function ajax_addElement( structure , args ) {
775                 
776         var i,
777                 start = 0,
778                 length = args.length,
779                 dataTypes = [ "*" ],
780                 dLength = 1,
781                 dataType,
782                 functors = [],
783                 first,
784                 append,
785                 list;
786                 
787         if ( length ) {
788                 
789                 first = jQuery.type( args[ 0 ] );
790                 
791                 if ( first === "object" ) {
792                         return ajax_selectOrExecute( structure , args[ 0 ] );
793                 }
794                 
795                 structure = jQuery.ajaxSettings[ structure ];
796                 
797                 if ( first !== "function" ) {
798                         
799                         dataTypes = args[ 0 ].toLowerCase().split(/\s+/);
800                         dLength = dataTypes.length;
801                         start = 1;
802                         
803                 }
804                 
805                 if ( dLength && start < length ) {
806                         
807                         functors = sliceFunc.call( args , start );
808                                         
809                         for( i = 0 ; i < dLength ; i++ ) {
810                                 
811                                 dataType = dataTypes[ i ];
812                                 
813                                 first = /^\+/.test( dataType );
814                                 
815                                 if (first) {
816                                         dataType = dataType.substr(1);
817                                 }
818                                 
819                                 if ( dataType !== "" ) {
820                                 
821                                         append = Array.prototype[ first ? "unshift" : "push" ];
822                                         list = structure[ dataType ] = structure[ dataType ] || [];
823                                         append.apply( list , functors );
824                                 }
825                         }
826                 }
827         }
828         
829         return jQuery.ajax;
830 }
831
832 // Install prefilter & transport methods
833 jQuery.each( [ "prefilter" , "transport" ] , function( _ , name ) {
834         _ = name + "s";
835         jQuery.ajax[ name ] = function() {
836                 return ajax_addElement( _ , arguments );
837         };
838 } );
839         
840 // Utility function that handles dataType when response is received
841 // (for those transports that can give text or xml responses)
842 function determineDataType( s , ct , text , xml ) {
843         
844         var autoDataType = s.autoDataType,
845                 type,
846                 regexp,
847                 dataTypes = s.dataTypes,
848                 transportDataType = dataTypes[0],
849                 response;
850         
851         // Auto (xml, json, script or text determined given headers)
852         if ( transportDataType === "*" ) {
853
854                 for ( type in autoDataType ) {
855                         if ( ( regexp = autoDataType[ type ] ) && regexp.test( ct ) ) {
856                                 transportDataType = dataTypes[0] = type;
857                                 break;
858                         }
859                 }                       
860         } 
861         
862         // xml and parsed as such
863         if ( transportDataType === "xml" &&
864                 xml &&
865                 xml.documentElement /* #4958 */ ) {
866                 
867                 response = xml;
868         
869         // Text response was provided
870         } else {
871                 
872                 response = text;
873                 
874                 // If it's not really text, defer to dataConverters
875                 if ( transportDataType !== "text" ) {
876                         dataTypes.unshift( "text" );
877                 }
878                 
879         }
880         
881         return response;
882 }       
883
884 /*
885  * Create the request object; Microsoft failed to properly
886  * implement the XMLHttpRequest in IE7 (can't request local files),
887  * so we use the ActiveXObject when it is available
888  * Additionally XMLHttpRequest can be disabled in IE7/IE8 so
889  * we need a fallback.
890  */
891 if ( window.ActiveXObject ) {
892         jQuery.ajaxSettings.xhr = function() {
893         if ( window.location.protocol !== "file:" ) {
894                 try {
895                         return new window.XMLHttpRequest();
896                 } catch( xhrError ) {}
897         }
898
899         try {
900                 return new window.ActiveXObject("Microsoft.XMLHTTP");
901         } catch( activeError ) {}
902         };
903 }
904
905 var testXHR = jQuery.ajaxSettings.xhr();
906
907 // Does this browser support XHR requests?
908 jQuery.support.ajax = !!testXHR;
909
910 // Does this browser support crossDomain XHR requests
911 jQuery.support.cors = testXHR && "withCredentials" in testXHR;
912
913 })( jQuery );