ajaxfileupload.js
jQuery.extend({createUploadIframe: function(id, uri){//create framevar frameId = 'jUploadFrame' + id;var iframeHtml = '<iframe id="' + frameId + '" name="' + frameId + '" style="position:absolute; top:-9999px; left:-9999px"';if(window.ActiveXObject){if(typeof uri== 'boolean'){iframeHtml += ' src="' + 'javascript:false' + '"';}else if(typeof uri== 'string'){iframeHtml += ' src="' + uri + '"';} }iframeHtml += ' />';jQuery(iframeHtml).appendTo(document.body);return jQuery('#' + frameId).get(0); },createUploadForm: function(id, fileElementId, data){//create form var formId = 'jUploadForm' + id;var fileId = 'jUploadFile' + id;var form = jQuery('<form action="" method="POST" name="' + formId + '" id="' + formId + '" enctype="multipart/form-data"></form>'); if(data){for(var i in data){jQuery('<input type="hidden" name="' + i + '" value="' + data[i] + '" />').appendTo(form);} } var oldElement = jQuery('#' + fileElementId);var newElement = jQuery(oldElement).clone();jQuery(oldElement).attr('id', fileId);jQuery(oldElement).before(newElement);jQuery(oldElement).appendTo(form);//set attributesjQuery(form).css('position', 'absolute');jQuery(form).css('top', '-1200px');jQuery(form).css('left', '-1200px');jQuery(form).appendTo('body'); return form;},ajaxFileUpload: function(s) {// TODO introduce global settings, allowing the client to modify them for all requests, not only timeout s = jQuery.extend({}, jQuery.ajaxSettings, s);var id = new Date().getTime() var form = jQuery.createUploadForm(id, s.fileElementId, (typeof(s.data)=='undefined'?false:s.data));var io = jQuery.createUploadIframe(id, s.secureuri);var frameId = 'jUploadFrame' + id;var formId = 'jUploadForm' + id; // Watch for a new set of requestsif ( s.global && ! jQuery.active++ ){jQuery.event.trigger( "ajaxStart" );} var requestDone = false;// Create the request objectvar xml = {} if ( s.global )jQuery.event.trigger("ajaxSend", [xml, s]);// Wait for a response to come backvar uploadCallback = function(isTimeout){ var io = document.getElementById(frameId);try { if(io.contentWindow){xml.responseText = io.contentWindow.document.body?io.contentWindow.document.body.innerHTML:null;xml.responseXML = io.contentWindow.document.XMLDocument?io.contentWindow.document.XMLDocument:io.contentWindow.document;}else if(io.contentDocument){xml.responseText = io.contentDocument.document.body?io.contentDocument.document.body.innerHTML:null;xml.responseXML = io.contentDocument.document.XMLDocument?io.contentDocument.document.XMLDocument:io.contentDocument.document;} }catch(e){jQuery.handleError(s, xml, null, e);}if ( xml || isTimeout == "timeout") { requestDone = true;var status;try {status = isTimeout != "timeout" ? "success" : "error";// Make sure that the request was successful or notmodifiedif ( status != "error" ){// process the data (runs the xml through httpData regardless of callback)var data = jQuery.uploadHttpData( xml, s.dataType ); // If a local callback was specified, fire it and pass it the dataif ( s.success )s.success( data, status );// Fire the global callbackif( s.global )jQuery.event.trigger( "ajaxSuccess", [xml, s] );} elsejQuery.handleError(s, xml, status);} catch(e) {status = "error";jQuery.handleError(s, xml, status, e);}// The request was completedif( s.global )jQuery.event.trigger( "ajaxComplete", [xml, s] );// Handle the global AJAX counterif ( s.global && ! --jQuery.active )jQuery.event.trigger( "ajaxStop" );// Process resultif ( s.complete )s.complete(xml, status);jQuery(io).unbind()setTimeout(function(){ try {jQuery(io).remove();jQuery(form).remove(); } catch(e) {jQuery.handleError(s, xml, null, e);} }, 100)xml = null}}// Timeout checkerif ( s.timeout > 0 ) {setTimeout(function(){// Check to see if the request is still happeningif( !requestDone ) uploadCallback( "timeout" );}, s.timeout);}try {var form = jQuery('#' + formId);jQuery(form).attr('action', s.url);jQuery(form).attr('method', 'POST');jQuery(form).attr('target', frameId);if(form.encoding){jQuery(form).attr('encoding', 'multipart/form-data'); }else{ jQuery(form).attr('enctype', 'multipart/form-data'); } jQuery(form).submit();} catch(e) { jQuery.handleError(s, xml, null, e);}jQuery('#' + frameId).load(uploadCallback );return {abort: function () {}}; },uploadHttpData: function( r, type ) {var data = !type;data = type == "xml" || data ? r.responseXML : r.responseText;// If the type is "script", eval it in global contextif ( type == "script" )jQuery.globalEval( data );// Get the JavaScript object, if JSON is used.if ( type == "json" )eval( "data = " + data );// evaluate scripts within htmlif ( type == "html" )jQuery("<div>").html(data).evalScripts();return data;},handleError: function( s, xhr, status, e ) {// If a local callback was specified, fire itif ( s.error ) {s.error.call( s.context || s, xhr, status, e );}// Fire the global callbackif ( s.global ) {(s.context ? jQuery(s.context) : jQuery.event).trigger( "ajaxError", [xhr, s, e] );}}})
注：如果出現
jQuery.handleError is not a function?原因是，經測試handlerError只在jquery-1.4.2之前的版本中存在，jquery-1.6 和1.7中都沒有這個函數了，因此在1.4.2中將這個函數復制到了ajaxFileUpload.js中，問題解決
handleError: function( s, xhr, status, e ) {
// If a local callback was specified, fire itif ( s.error ) {s.error.call( s.context || s, xhr, status, e );}// Fire the global callbackif ( s.global ) {(s.context ? jQuery(s.context) : jQuery.event).trigger( "ajaxError", [xhr, s, e] );}},
問題2：一直得到error ，無法執行指定的success方法。通過追蹤ajaxFileUpload的執行過程發現，在調用它自身的uploadHttpData函數時，當執行if（type=="json") eval("data = "+data);
會拋出異常，導致在處理異常的時候將status = "error" 因此一直執行error方法。
上網查詢，得知eval函數是用來執行一段js代碼，而并不是如我所想的反解json串
eval("data = "+data);的意思是 將data 賦值給 data參數 ，但是當我返回給頁面的是一個簡單的字符串，比如"OK" ，時，這樣寫就拋出異常。最后改為 eval("data = \" "+data+" \" ");即將返回的數據用雙引號引起來當作字符串，然后賦給 data 。終于成功了。。。
