{ var r20 = /%20/g, //全部空格 rbracket = /\[\]$/, //结尾位置匹配中括号 rCRLF = /\r?\n/g, rsubmitterTypes = /^(?:submit|button|image|reset|file)$/i, rsubmittable = /^(?:input|select|textarea|keygen)/i; jQuery.fn.extend({ serialize: function() { return jQuery.param( this.serializeArray() ); }, // console.log($('#form1').serializeArray());//[{'name':'a','value':'1'},{'name':'b','value':'2'}] serializeArray: function() { return this.map(function(){//map是数组都执行函数，返回结果集合 //只有表单有elements属性。 var elements = jQuery.prop( this, "elements" ); return elements ? jQuery.makeArray( elements ) : this; }) .filter(function(){ var type = this.type; // Use .is(":disabled") so that fieldset[disabled] works return this.name && !jQuery( this ).is( ":disabled" ) && rsubmittable.test( this.nodeName ) && !rsubmitterTypes.test( type ) && ( this.checked || !manipulation_rcheckableType.test( type ) ); }) .map(function( i, elem ){ var val = jQuery( this ).val(); return val == null ? null : jQuery.isArray( val ) ? jQuery.map( val, function( val ){ return { name: elem.name, value: val.replace( rCRLF, "\r\n" ) }; }) : { name: elem.name, value: val.replace( rCRLF, "\r\n" ) }; }).get(); } }); //json对象、数组对象序列化成字符串 //$.param( [ {'name':1,'value':2} ] );//1=2,name为key,value为value jQuery.param = function( a, traditional ) { var prefix, s = [], //定义一个函数 add = function( key, value ) { //是函数就让函数执行，得到返回值 value = jQuery.isFunction( value ) ? value() : ( value == null ? "" : value ); //编码 s[ s.length ] = encodeURIComponent( key ) + "=" + encodeURIComponent( value ); }; // Set traditional to true for jQuery <= 1.3.2 behavior. if ( traditional === undefined ) { traditional = jQuery.ajaxSettings && jQuery.ajaxSettings.traditional; } /* var $a = $( [ {'name':1,'value':2},{'name':3,'value':4} ] )}; console.log( $.param($a) ) */ if ( jQuery.isArray( a ) || ( a.jquery && !jQuery.isPlainObject( a ) ) ) { // Serialize the form elements jQuery.each( a, function() { add( this.name, this.value );//每一个a的name和value属性， }); } else { // a={'name':[1,3],'value':2}，a={'name':{'a1':1,'a3':3},'value':2} add是回调进行拼接 for ( prefix in a ) { buildParams( prefix, a[ prefix ], traditional, add ); } } // 通过&链接， return s.join( "&" ).replace( r20, "+" ); }; //buildParams（name，[1,3]，traditional,add()） ////buildParams（name，{'a1':1,'a3':3}，traditional,add()） function buildParams( prefix, obj, traditional, add ) { var name; if ( jQuery.isArray( obj ) ) { jQuery.each( obj, function( i, v ) { if ( traditional || rbracket.test( prefix ) ) {//传统方式 add( prefix, v ); } else { // 多用三目运算符 buildParams( prefix + "[" + ( typeof v === "object" ? i : "" ) + "]", v, traditional, add ); } }); } else if ( !traditional && jQuery.type( obj ) === "object" ) { // Serialize object item. for ( name in obj ) { buildParams( prefix + "[" + name + "]", obj[ name ], traditional, add ); } } else { // 不是数组不是对象，普通方式 add( prefix, obj ); } } var // Document location ajaxLocParts, ajaxLocation, ajax_nonce = jQuery.now(), ajax_rquery = /\?/, rhash = /#.*$/, rts = /([?&])_=[^&]*/, rheaders = /^(.*?):[ \t]*([^\r\n]*)$/mg, // #7653, #8125, #8152: local protocol detection rlocalProtocol = /^(?:about|app|app-storage|.+-extension|file|res|widget):$/, rnoContent = /^(?:GET|HEAD)$/, rprotocol = /^\/\//, rurl = /^([\w.+-]+:)(?:\/\/([^\/?#:]*)(?::(\d+)|)|)/, // Keep a copy of the old load method _load = jQuery.fn.load, /* Prefilters * 1) They are useful to introduce custom dataTypes (see ajax/jsonp.js for an example) * 2) These are called: * - BEFORE asking for a transport * - AFTER param serialization (s.data is a string if s.processData is true) * 3) key is the dataType * 4) the catchall symbol "*" can be used * 5) execution will start with transport dataType and THEN continue down to "*" if needed */ //预过滤器，在发送ajax之前做一些处理 prefilters = {}, /* Transports bindings * 1) key is the dataType * 2) the catchall symbol "*" can be used * 3) selection will start with transport dataType and THEN go to "*" if needed */ //分发器， transports = {}, // Avoid comment-prolog char sequence (#10098); must appease lint and evade compression allTypes = "*/".concat("*"); // #8138, IE may throw an exception when accessing // a field from window.location if document.domain has been set try { ajaxLocation = location.href; } catch( e ) { // 兼容性，动态创建a标签，a标签的href是空，然后就可以获取当前页面地址 ajaxLocation = document.createElement( "a" ); ajaxLocation.href = ""; ajaxLocation = ajaxLocation.href; } // Segment location into parts ajaxLocParts = rurl.exec( ajaxLocation.toLowerCase() ) || []; // Base "constructor" for jQuery.ajaxPrefilter and jQuery.ajaxTransport function addToPrefiltersOrTransports( structure ) { // dataTypeExpression is optional and defaults to "*" return function( dataTypeExpression, func ) { if ( typeof dataTypeExpression !== "string" ) { func = dataTypeExpression; dataTypeExpression = "*"; } var dataType, i = 0, dataTypes = dataTypeExpression.toLowerCase().match( core_rnotwhite ) || []; if ( jQuery.isFunction( func ) ) { // For each dataType in the dataTypeExpression while ( (dataType = dataTypes[i++]) ) { // Prepend if requested if ( dataType[0] === "+" ) { dataType = dataType.slice( 1 ) || "*"; (structure[ dataType ] = structure[ dataType ] || []).unshift( func ); // Otherwise append } else { (structure[ dataType ] = structure[ dataType ] || []).push( func ); } } } }; } // Base inspection function for prefilters and transports function inspectPrefiltersOrTransports( structure, options, originalOptions, jqXHR ) { var inspected = {}, seekingTransport = ( structure === transports ); function inspect( dataType ) { var selected; inspected[ dataType ] = true; jQuery.each( structure[ dataType ] || [], function( _, prefilterOrFactory ) { var dataTypeOrTransport = prefilterOrFactory( options, originalOptions, jqXHR ); if( typeof dataTypeOrTransport === "string" && !seekingTransport && !inspected[ dataTypeOrTransport ] ) { options.dataTypes.unshift( dataTypeOrTransport ); inspect( dataTypeOrTransport ); return false; } else if ( seekingTransport ) { return !( selected = dataTypeOrTransport ); } }); return selected; } return inspect( options.dataTypes[ 0 ] ) || !inspected[ "*" ] && inspect( "*" ); } // 继承 function ajaxExtend( target, src ) { var key, deep, flatOptions = jQuery.ajaxSettings.flatOptions || {}; for ( key in src ) { if ( src[ key ] !== undefined ) { ( flatOptions[ key ] ? target : ( deep || (deep = {}) ) )[ key ] = src[ key ]; } } if ( deep ) { jQuery.extend( true, target, deep ); } return target; } // $('#div1').load("1.html ol,{'name':'hello'}",function(a,b,c){}) jQuery.fn.load = function( url, params, callback ) { if ( typeof url !== "string" && _load ) { return _load.apply( this, arguments ); } var selector, type, response, self = this, off = url.indexOf(" "); if ( off >= 0 ) { selector = url.slice( off ); url = url.slice( 0, off ); } // If it's a function if ( jQuery.isFunction( params ) ) { // We assume that it's the callback callback = params; params = undefined; // Otherwise, build a param string } else if ( params && typeof params === "object" ) { type = "POST";//对象是post方式 } // If we have elements to modify, make the request if ( self.length > 0 ) { jQuery.ajax({ url: url, type: type,//默认是get dataType: "html",//返回数据类型 data: params //传输数据 }).done(function( responseText ) {//responseText返回的数据 response = arguments; //self.html()添加到本元素的html内容中 self.html( selector ? //有过滤器 //动态创建div,添加返回的html,查找过滤器 jQuery("<div>").append( jQuery.parseHTML( responseText ) ).find( selector ) : // Otherwise use the full result responseText ); //complete是完成不管成功失败 }).complete( callback && function( jqXHR, status ) { self.each( callback, response || [ jqXHR.responseText, status, jqXHR ] ); }); } return this; }; // Attach a bunch of functions for handling common AJAX events jQuery.each( [ "ajaxStart", "ajaxStop", "ajaxComplete", "ajaxError", "ajaxSuccess", "ajaxSend" ], function( i, type ){ jQuery.fn[ type ] = function( fn ){ return this.on( type, fn ); }; }); jQuery.extend({ // Counter for holding the number of active queries active: 0, // Last-Modified header cache for next request lastModified: {}, etag: {}, //ajax默认参数 ajaxSettings: { url: ajaxLocation,//ajaxLocation = location.href;默认是当前页面地址 type: "GET", isLocal: rlocalProtocol.test( ajaxLocParts[ 1 ] ), //是否本地 global: true, //是否能触发全局事件参数 processData: true, async: true, contentType: "application/x-www-form-urlencoded; charset=UTF-8",//数据编码操作， //注释是一样的，注释不写就是undefined， /* timeout: 0, //超时处理，超时就提示是否继续等待还是离开还是刷新 data: null, dataType: null, username: null, //服务器的验证 password: null, cache: null, //cache:false,请求后面加一个时间戳，不会有缓存 throws: false, // traditional: false, //传统模式 headers: {}, */ accepts: { "*": allTypes, text: "text/plain", html: "text/html", xml: "application/xml, text/xml", json: "application/json, text/javascript" }, //检测响应头信息，判断返回的类型。 contents: { xml: /xml/, html: /html/, json: /json/ }, responseFields: { xml: "responseXML", text: "responseText", json: "responseJSON" }, // 根据返回的响应头信息，做不同的转换。 converters: { // Convert anything to text "* text": String, // Text to html (true = no transformation) "text html": true, // Evaluate text as a json expression "text json": jQuery.parseJSON, // Parse text as xml "text xml": jQuery.parseXML }, // For options that shouldn't be deep extended: // you can add your own custom options here if // and when you create one that shouldn't be // deep extended (see ajaxExtend) flatOptions: { url: true, context: true } }, // 对json继承的封装 ajaxSetup: function( target, settings ) { return settings ? //继承json过去 ajaxExtend( ajaxExtend( target, jQuery.ajaxSettings ), settings ) : // Extending ajaxSettings ajaxExtend( jQuery.ajaxSettings, target ); }, ajaxPrefilter: addToPrefiltersOrTransports( prefilters ), ajaxTransport: addToPrefiltersOrTransports( transports ), // Main method /* $.ajax({ url:url, type:'post', success : function(){}, error:function(){} }); $.ajax('url',{ type:'post', success : function(){}, error:function(){} }); */ ajax: function( url, options ) {//url是地址，options是json if ( typeof url === "object" ) {//url是json就赋值给options options = url; url = undefined; } // Force options to be an object options = options || {}; var transport, // URL without anti-cache param cacheURL, // Response headers responseHeadersString, responseHeaders, // timeout handle timeoutTimer, // Cross-domain detection vars parts, // To know if global events are to be dispatched fireGlobals, // Loop variable i, //options覆盖默认参数，继承 s = jQuery.ajaxSetup( {}, options ), // Callbacks context callbackContext = s.context || s, // Context for global events is callbackContext if it is a DOM node or jQuery collection globalEventContext = s.context && ( callbackContext.nodeType || callbackContext.jquery ) ? jQuery( callbackContext ) : jQuery.event, // 延迟对象，回调对象 deferred = jQuery.Deferred(), completeDeferred = jQuery.Callbacks("once memory"), // Status-dependent callbacks statusCode = s.statusCode || {}, // Headers (they are sent all at once) requestHeaders = {}, requestHeadersNames = {}, // The jqXHR state state = 0, // Default abort message strAbort = "canceled", // Fake xhr jqXHR = { readyState: 0,//0--4,4的时候就是完成了 // 获取响应头 getResponseHeader: function( key ) { var match; if ( state === 2 ) { if ( !responseHeaders ) { responseHeaders = {}; while ( (match = rheaders.exec( responseHeadersString )) ) { responseHeaders[ match[1].toLowerCase() ] = match[ 2 ]; } } match = responseHeaders[ key.toLowerCase() ]; } return match == null ? null : match; }, // Raw string getAllResponseHeaders: function() { return state === 2 ? responseHeadersString : null; }, // 设置请求头 setRequestHeader: function( name, value ) { var lname = name.toLowerCase(); if ( !state ) { name = requestHeadersNames[ lname ] = requestHeadersNames[ lname ] || name; requestHeaders[ name ] = value; } return this; }, // Overrides response content-type header overrideMimeType: function( type ) { if ( !state ) { s.mimeType = type; } return this; }, // Status-dependent callbacks statusCode: function( map ) { var code; if ( map ) { if ( state < 2 ) { for ( code in map ) { // Lazy-add the new callback in a way that preserves old ones statusCode[ code ] = [ statusCode[ code ], map[ code ] ]; } } else { // Execute the appropriate callbacks jqXHR.always( map[ jqXHR.status ] ); } } return this; }, // 错误的时候，例如超时，报错 abort: function( statusText ) { var finalText = statusText || strAbort; if ( transport ) { transport.abort( finalText ); } done( 0, finalText ); return this; } }; // 方法加进去 deferred.promise( jqXHR ).complete = completeDeferred.add; jqXHR.success = jqXHR.done; jqXHR.error = jqXHR.fail; // 对url处理， s.url = ( ( url || s.url || ajaxLocation ) + "" ).replace( rhash, "" ) .replace( rprotocol, ajaxLocParts[ 1 ] + "//" ); // Alias method option to type as per ticket #12004 s.type = options.method || options.type || s.method || s.type; // Extract dataTypes list s.dataTypes = jQuery.trim( s.dataType || "*" ).toLowerCase().match( core_rnotwhite ) || [""]; // 跨域处理，不跟本网页是同一个主机地址。 if ( s.crossDomain == null ) { parts = rurl.exec( s.url.toLowerCase() ); s.crossDomain = !!( parts && ( parts[ 1 ] !== ajaxLocParts[ 1 ] || parts[ 2 ] !== ajaxLocParts[ 2 ] || ( parts[ 3 ] || ( parts[ 1 ] === "http:" ? "80" : "443" ) ) !== ( ajaxLocParts[ 3 ] || ( ajaxLocParts[ 1 ] === "http:" ? "80" : "443" ) ) ) ); } // Convert data if not already a string if ( s.data && s.processData && typeof s.data !== "string" ) { s.data = jQuery.param( s.data, s.traditional ); } // 触发回调 inspectPrefiltersOrTransports( prefilters, s, options, jqXHR ); // 请求完成了 if ( state === 2 ) { return jqXHR; } // We can fire global events as of now if asked to fireGlobals = s.global; // Watch for a new set of requests if ( fireGlobals && jQuery.active++ === 0 ) { jQuery.event.trigger("ajaxStart"); } // Uppercase the type s.type = s.type.toUpperCase(); // Determine if request has content s.hasContent = !rnoContent.test( s.type ); // Save the URL in case we're toying with the If-Modified-Since // and/or If-None-Match header later on cacheURL = s.url; // More options handling for requests with no content if ( !s.hasContent ) { // If data is available, append data to url if ( s.data ) { cacheURL = ( s.url += ( ajax_rquery.test( cacheURL ) ? "&" : "?" ) + s.data ); // #9682: remove data so that it's not used in an eventual retry delete s.data; } // 不缓存就添加随机数 if ( s.cache === false ) { s.url = rts.test( cacheURL ) ? // If there is already a '_' parameter, set its value cacheURL.replace( rts, "$1_=" + ajax_nonce++ ) : // Otherwise add one to the end cacheURL + ( ajax_rquery.test( cacheURL ) ? "&" : "?" ) + "_=" + ajax_nonce++; } } // 设置头信息，数据没有改变走缓存，通过后端配合，数据改变发起新的请求。 if ( s.ifModified ) { if ( jQuery.lastModified[ cacheURL ] ) { jqXHR.setRequestHeader( "If-Modified-Since", jQuery.lastModified[ cacheURL ] ); } if ( jQuery.etag[ cacheURL ] ) { jqXHR.setRequestHeader( "If-None-Match", jQuery.etag[ cacheURL ] ); } } // Set the correct header, if data is being sent if ( s.data && s.hasContent && s.contentType !== false || options.contentType ) { jqXHR.setRequestHeader( "Content-Type", s.contentType ); } // 设置请求类型 jqXHR.setRequestHeader( "Accept", s.dataTypes[ 0 ] && s.accepts[ s.dataTypes[0] ] ? s.accepts[ s.dataTypes[0] ] + ( s.dataTypes[ 0 ] !== "*" ? ", " + allTypes + "; q=0.01" : "" ) : s.accepts[ "*" ] ); // Check for headers option for ( i in s.headers ) { jqXHR.setRequestHeader( i, s.headers[ i ] ); } // Allow custom headers/mimetypes and early abort if ( s.beforeSend && ( s.beforeSend.call( callbackContext, jqXHR, s ) === false || state === 2 ) ) { // Abort if not done already and return return jqXHR.abort(); } // aborting is no longer a cancellation strAbort = "abort"; // Install callbacks on deferreds for ( i in { success: 1, error: 1, complete: 1 } ) { jqXHR[ i ]( s[ i ] ); } // Get transport transport = inspectPrefiltersOrTransports( transports, s, options, jqXHR ); // If no transport, we auto-abort if ( !transport ) { done( -1, "No Transport" ); } else { jqXHR.readyState = 1; // Send global event if ( fireGlobals ) { globalEventContext.trigger( "ajaxSend", [ jqXHR, s ] ); } // Timeout if ( s.async && s.timeout > 0 ) { timeoutTimer = setTimeout(function() { jqXHR.abort("timeout"); }, s.timeout ); } try { state = 1; transport.send( requestHeaders, done ); } catch ( e ) { // Propagate exception as error if not done if ( state < 2 ) { done( -1, e ); // Simply rethrow otherwise } else { throw e; } } } // Callback for when everything is done function done( status, nativeStatusText, responses, headers ) { var isSuccess, success, error, response, modified, statusText = nativeStatusText; // Called once if ( state === 2 ) { return; } // State is "done" now state = 2; // Clear timeout if it exists if ( timeoutTimer ) { clearTimeout( timeoutTimer ); } // Dereference transport for early garbage collection // (no matter how long the jqXHR object will be used) transport = undefined; // Cache response headers responseHeadersString = headers || ""; // Set readyState jqXHR.readyState = status > 0 ? 4 : 0; // Determine if successful isSuccess = status >= 200 && status < 300 || status === 304; // Get response data if ( responses ) { response = ajaxHandleResponses( s, jqXHR, responses ); } // Convert no matter what (that way responseXXX fields are always set) response = ajaxConvert( s, response, jqXHR, isSuccess ); // If successful, handle type chaining if ( isSuccess ) { // Set the If-Modified-Since and/or If-None-Match header, if in ifModified mode. if ( s.ifModified ) { modified = jqXHR.getResponseHeader("Last-Modified"); if ( modified ) { jQuery.lastModified[ cacheURL ] = modified; } modified = jqXHR.getResponseHeader("etag"); if ( modified ) { jQuery.etag[ cacheURL ] = modified; } } // if no content if ( status === 204 || s.type === "HEAD" ) { statusText = "nocontent"; // if not modified } else if ( status === 304 ) { statusText = "notmodified"; // If we have data, let's convert it } else { statusText = response.state; success = response.data; error = response.error; isSuccess = !error; } } else { // We extract error from statusText // then normalize statusText and status for non-aborts error = statusText; if ( status || !statusText ) { statusText = "error"; if ( status < 0 ) { status = 0; } } } // Set data for the fake xhr object jqXHR.status = status; jqXHR.statusText = ( nativeStatusText || statusText ) + ""; // Success/Error if ( isSuccess ) { deferred.resolveWith( callbackContext, [ success, statusText, jqXHR ] ); } else { deferred.rejectWith( callbackContext, [ jqXHR, statusText, error ] ); } // Status-dependent callbacks jqXHR.statusCode( statusCode ); statusCode = undefined; if ( fireGlobals ) { globalEventContext.trigger( isSuccess ? "ajaxSuccess" : "ajaxError", [ jqXHR, s, isSuccess ? success : error ] ); } // Complete completeDeferred.fireWith( callbackContext, [ jqXHR, statusText ] ); if ( fireGlobals ) { globalEventContext.trigger( "ajaxComplete", [ jqXHR, s ] ); // Handle the global AJAX counter if ( !( --jQuery.active ) ) { jQuery.event.trigger("ajaxStop"); } } } //ajax方法结束后，返回jqXHR对象，$.ajax()方法后面就可以调用done、fail方法，$.ajax({url:url}).done().fail(); return jqXHR; }, getJSON: function( url, data, callback ) { return jQuery.get( url, data, callback, "json" );//调用jQuery.ajax() }, getScript: function( url, callback ) {//请求js不传递参数 return jQuery.get( url, undefined, callback, "script" ); //调用jQuery.ajax() } }); //["get","post"]每一个元素调用function( i, method )，i是索引method是'get'、'post' jQuery.each( [ "get", "post" ], function( i, method ) { //get，post挂载到jQuery静态方法,通过中括号挂载。 //$.get('url',{'aa':123},function(){'成功回调'},'返回数据类型xml、json') jQuery[ method ] = function( url, data, callback, type ) { // shift arguments if data argument was omitted if ( jQuery.isFunction( data ) ) { type = type || callback; callback = data; data = undefined; } return jQuery.ajax({ url: url, type: method, dataType: type, data: data, success: callback }); }; }); /* Handles responses to an ajax request: * - finds the right dataType (mediates between content-type and expected dataType) * - returns the corresponding response */ function ajaxHandleResponses( s, jqXHR, responses ) { var ct, type, finalDataType, firstDataType, contents = s.contents, dataTypes = s.dataTypes; // Remove auto dataType and get content-type in the process while( dataTypes[ 0 ] === "*" ) { dataTypes.shift(); if ( ct === undefined ) { ct = s.mimeType || jqXHR.getResponseHeader("Content-Type"); } } // Check if we're dealing with a known content-type if ( ct ) { for ( type in contents ) { if ( contents[ type ] && contents[ type ].test( ct ) ) { dataTypes.unshift( type ); break; } } } // Check to see if we have a response for the expected dataType if ( dataTypes[ 0 ] in responses ) { finalDataType = dataTypes[ 0 ]; } else { // Try convertible dataTypes for ( type in responses ) { if ( !dataTypes[ 0 ] || s.converters[ type + " " + dataTypes[0] ] ) { finalDataType = type; break; } if ( !firstDataType ) { firstDataType = type; } } // Or just use first one finalDataType = finalDataType || firstDataType; } // If we found a dataType // We add the dataType to the list if needed // and return the corresponding response if ( finalDataType ) { if ( finalDataType !== dataTypes[ 0 ] ) { dataTypes.unshift( finalDataType ); } return responses[ finalDataType ]; } } //类型转换器，匹配返回的数据类型 function ajaxConvert( s, response, jqXHR, isSuccess ) { var conv2, current, conv, tmp, prev, converters = {}, // Work with a copy of dataTypes in case we need to modify it for conversion dataTypes = s.dataTypes.slice(); // Create converters map with lowercased keys if ( dataTypes[ 1 ] ) { for ( conv in s.converters ) { converters[ conv.toLowerCase() ] = s.converters[ conv ]; } } current = dataTypes.shift(); // Convert to each sequential dataType while ( current ) { if ( s.responseFields[ current ] ) { jqXHR[ s.responseFields[ current ] ] = response; } // Apply the dataFilter if provided if ( !prev && isSuccess && s.dataFilter ) { response = s.dataFilter( response, s.dataType ); } prev = current; current = dataTypes.shift(); if ( current ) { // There's only work to do if current dataType is non-auto if ( current === "*" ) { current = prev; // Convert response if prev dataType is non-auto and differs from current } else if ( prev !== "*" && prev !== current ) { // Seek a direct converter conv = converters[ prev + " " + current ] || converters[ "* " + current ]; // If none found, seek a pair if ( !conv ) { for ( conv2 in converters ) { // If conv2 outputs current tmp = conv2.split( " " ); if ( tmp[ 1 ] === current ) { // If prev can be converted to accepted input conv = converters[ prev + " " + tmp[ 0 ] ] || converters[ "* " + tmp[ 0 ] ]; if ( conv ) { // Condense equivalence converters if ( conv === true ) { conv = converters[ conv2 ]; // Otherwise, insert the intermediate dataType } else if ( converters[ conv2 ] !== true ) { current = tmp[ 0 ]; dataTypes.unshift( tmp[ 1 ] ); } break; } } } } // Apply converter (if not an equivalence) if ( conv !== true ) { // Unless errors are allowed to bubble, catch and return them if ( conv && s[ "throws" ] ) { response = conv( response ); } else { try { response = conv( response ); } catch ( e ) { return { state: "parsererror", error: conv ? e : "No conversion from " + prev + " to " + current }; } } } } } } return { state: "success", data: response }; } // Install script dataType jQuery.ajaxSetup({ accepts: { script: "text/javascript, application/javascript, application/ecmascript, application/x-ecmascript" }, contents: { script: /(?:java|ecma)script/ }, converters: { "text script": function( text ) { jQuery.globalEval( text ); return text; } } }); // 发送ajax之前对数据做处理 jQuery.ajaxPrefilter( "script", function( s ) { if ( s.cache === undefined ) { s.cache = false; } if ( s.crossDomain ) { s.type = "GET"; } }); // Bind script tag hack transport jQuery.ajaxTransport( "script", function( s ) { // This transport only deals with cross domain requests if ( s.crossDomain ) { var script, callback; return { send: function( _, complete ) { script = jQuery("<script>").prop({ async: true, charset: s.scriptCharset, src: s.url }).on( "load error", callback = function( evt ) { script.remove(); callback = null; if ( evt ) { complete( evt.type === "error" ? 404 : 200, evt.type ); } } ); document.head.appendChild( script[ 0 ] ); }, abort: function() { if ( callback ) { callback(); } } }; } }); var oldCallbacks = [], rjsonp = /(=)\?(?=&|$)|\?\?/; // Default jsonp settings jQuery.ajaxSetup({ jsonp: "callback", jsonpCallback: function() { var callback = oldCallbacks.pop() || ( jQuery.expando + "_" + ( ajax_nonce++ ) ); this[ callback ] = true; return callback; } }); // Detect, normalize options and install callbacks for jsonp requests jQuery.ajaxPrefilter( "json jsonp", function( s, originalSettings, jqXHR ) { var callbackName, overwritten, responseContainer, jsonProp = s.jsonp !== false && ( rjsonp.test( s.url ) ? "url" : typeof s.data === "string" && !( s.contentType || "" ).indexOf("application/x-www-form-urlencoded") && rjsonp.test( s.data ) && "data" ); // Handle iff the expected data type is "jsonp" or we have a parameter to set if ( jsonProp || s.dataTypes[ 0 ] === "jsonp" ) { // Get callback name, remembering preexisting value associated with it callbackName = s.jsonpCallback = jQuery.isFunction( s.jsonpCallback ) ? s.jsonpCallback() : s.jsonpCallback; // Insert callback into url or form data if ( jsonProp ) { s[ jsonProp ] = s[ jsonProp ].replace( rjsonp, "$1" + callbackName ); } else if ( s.jsonp !== false ) { s.url += ( ajax_rquery.test( s.url ) ? "&" : "?" ) + s.jsonp + "=" + callbackName; } // Use data converter to retrieve json after script execution s.converters["script json"] = function() { if ( !responseContainer ) { jQuery.error( callbackName + " was not called" ); } return responseContainer[ 0 ]; }; // force json dataType s.dataTypes[ 0 ] = "json"; // Install callback overwritten = window[ callbackName ]; window[ callbackName ] = function() { responseContainer = arguments; }; // Clean-up function (fires after converters) jqXHR.always(function() { // Restore preexisting value window[ callbackName ] = overwritten; // Save back as free if ( s[ callbackName ] ) { // make sure that re-using the options doesn't screw things around s.jsonpCallback = originalSettings.jsonpCallback; // save the callback name for future use oldCallbacks.push( callbackName ); } // Call if it was a function and we have a response if ( responseContainer && jQuery.isFunction( overwritten ) ) { overwritten( responseContainer[ 0 ] ); } responseContainer = overwritten = undefined; }); // Delegate to script return "script"; } }); jQuery.ajaxSettings.xhr = function() { try { return new XMLHttpRequest(); } catch( e ) {} }; var xhrSupported = jQuery.ajaxSettings.xhr(), xhrSuccessStatus = { // file protocol always yields status code 0, assume 200 0: 200, // Support: IE9 // #1450: sometimes IE returns 1223 when it should be 204 1223: 204 }, // Support: IE9 // We need to keep track of outbound xhr and abort them manually // because IE is not smart enough to do it all by itself xhrId = 0, xhrCallbacks = {}; if ( window.ActiveXObject ) { jQuery( window ).on( "unload", function() { for( var key in xhrCallbacks ) { xhrCallbacks[ key ](); } xhrCallbacks = undefined; }); } jQuery.support.cors = !!xhrSupported && ( "withCredentials" in xhrSupported ); jQuery.support.ajax = xhrSupported = !!xhrSupported; jQuery.ajaxTransport(function( options ) { var callback; // Cross domain only allowed if supported through XMLHttpRequest if ( jQuery.support.cors || xhrSupported && !options.crossDomain ) { return { send: function( headers, complete ) { var i, id, //xhr是原生XMLHttpRequest对象 xhr = options.xhr(); xhr.open( options.type, options.url, options.async, options.username, options.password ); // Apply custom fields if provided if ( options.xhrFields ) { for ( i in options.xhrFields ) { xhr[ i ] = options.xhrFields[ i ]; } } // 跨域处理 if ( options.mimeType && xhr.overrideMimeType ) { xhr.overrideMimeType( options.mimeType ); } // X-Requested-With header // For cross-domain requests, seeing as conditions for a preflight are // akin to a jigsaw puzzle, we simply never set it to be sure. // (it can always be set on a per-request basis or even using ajaxSetup) // For same-domain requests, won't change header if already provided. if ( !options.crossDomain && !headers["X-Requested-With"] ) { headers["X-Requested-With"] = "XMLHttpRequest"; } // Set headers for ( i in headers ) { xhr.setRequestHeader( i, headers[ i ] ); } // Callback callback = function( type ) { return function() { if ( callback ) { delete xhrCallbacks[ id ]; callback = xhr.onload = xhr.onerror = null; if ( type === "abort" ) { xhr.abort(); } else if ( type === "error" ) { complete( // file protocol always yields status 0, assume 404 xhr.status || 404, xhr.statusText ); } else { complete( xhrSuccessStatus[ xhr.status ] || xhr.status, xhr.statusText, // Support: IE9 // #11426: When requesting binary data, IE9 will throw an exception // on any attempt to access responseText typeof xhr.responseText === "string" ? { text: xhr.responseText } : undefined, xhr.getAllResponseHeaders() ); } } }; }; // 真正完成才会走onload xhr.onload = callback(); xhr.onerror = callback("error"); // Create the abort callback callback = xhrCallbacks[( id = xhrId++ )] = callback("abort"); // Do send the request // This may raise an exception which is actually // handled in jQuery.ajax (so no try/catch here) //发送 xhr.send( options.hasContent && options.data || null ); }, abort: function() { if ( callback ) { callback(); } } }; } }); }
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