最近在做一个项目需要实现异步上传图片,在网上找了很多资料后,采用了ajaxfileupload可以实现,以下是核心代码:
jsp:
<!-- 上传窗口 --> <div id="uploadPicWindow" class="easyui-window" title="上传图片" style="width:420px;height:220px;padding:20px;background:#fafafa;" data-options="iconCls:'icon-save',closable:true, collapsible:true,minimizable:true,maximizable:true"> <form id="picForm" action="" method="post"> <div style="margin-bottom:20px"> 图片名称: <input type="text" name="name" id="picName" class="easyui-textbox" style="width:80%" data-options="required:true,validType:'stringCheck'"/> </div> <br/> <div style="margin-bottom:20px"> 选择图片: <input type="file" name="file" id="file" data-options="prompt:'Choose a file...'" style="width:80%"/> </div> <div id="picTip"></div> <div id="formWindowfooterPic1" style="padding:5px;text-align:right;"> <a href="#" onclick="submitPic();" class="easyui-linkbutton" data-options="iconCls:'icon-save'">提交</a> </div> </form> </div>
js:
//新建或编辑 保存提交 function submitPic(){ if(!$("#picForm").form('validate')){ return false; } var projectId = $("#projectId").val(); var name=$("#picName").val(); var type="1";//展示图片 var f = $("#file").val(); if(f==null||f==""){ $("#picTip").html("<span style='color:Red'>错误提示:上传文件不能为空,请重新选择文件</span>"); return false; }else{ var extname = f.substring(f.lastIndexOf(".")+1,f.length); extname = extname.toLowerCase();//处理了大小写 if(extname!= "jpeg"&&extname!= "jpg"&&extname!= "gif"&&extname!= "png"){ $("#picTip").html("<span style='color:Red'>错误提示:格式不正确,支持的图片格式为:JPEG、GIF、PNG!</span>"); return false; } } var file = document.getElementById("file").files; var size = file[0].size; if(size>2097152){ $("#picTip").html("<span style='color:Red'>错误提示:所选择的图片太大,图片大小最多支持2M!</span>"); return false; } ajaxFileUploadPic(projectId,name,type); } function ajaxFileUploadPic(projectId,name,type) { $.ajaxFileUpload({ url : '${ctx}/projectPic/saveorupdate.jhtml?projectId='+projectId+'&name='+name+'&type='+type, //用于文件上传的服务器端请求地址 secureuri : false, //一般设置为false fileElementId : 'file', //文件上传空间的id属性 <input type="file" id="file" name="file" /> type : 'post', dataType : 'json', //返回值类型 一般设置为json success : function(data, status) //服务器成功响应处理函数 { $("#picList").datagrid('reload'); $('#uploadPicWindow').window('close'); // alert(data.msg); }, error : function(data, status, e)//服务器响应失败处理函数 { $("#picList").datagrid('reload'); $('#uploadPicWindow').window('close'); // alert(data.msg); } }); return false; }
jQuery.extend({ createUploadIframe: function(id, uri) { //create frame var 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 attributes jQuery(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 requests if ( s.global && ! jQuery.active++ ) { jQuery.event.trigger( "ajaxStart" ); } var requestDone = false; // Create the request object var xml = {} if ( s.global ) jQuery.event.trigger("ajaxSend", [xml, s]); // Wait for a response to come back var 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 notmodified if ( 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 data if ( s.success ) s.success( data, status ); // Fire the global callback if( s.global ) jQuery.event.trigger( "ajaxSuccess", [xml, s] ); } else jQuery.handleError(s, xml, status); } catch(e) { status = "error"; jQuery.handleError(s, xml, status, e); } // The request was completed if( s.global ) jQuery.event.trigger( "ajaxComplete", [xml, s] ); // Handle the global AJAX counter if ( s.global && ! --jQuery.active ) jQuery.event.trigger( "ajaxStop" ); // Process result if ( 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 checker if ( s.timeout > 0 ) { setTimeout(function(){ // Check to see if the request is still happening if( !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 context if ( type == "script" ) jQuery.globalEval( data ); // Get the JavaScript object, if JSON is used. if ( type == "json" ) eval( "data = " + data ); // evaluate scripts within html if ( type == "html" ) jQuery("<div>").html(data).evalScripts(); return data; }, handleError: function( s, xhr, status, e ) { // If a local callback was specified, fire it if ( s.error ) { s.error.call( s.context || s, xhr, status, e ); } // Fire the global callback if ( s.global ) { (s.context ? jQuery(s.context) : jQuery.event).trigger( "ajaxError", [xhr, s, e] ); } } })
注:如果出现
jQuery.handleError is not a function
原因是,经测试handlerError只在jquery-1.4.2之前的版本中存在,jquery-1.6 和1.7中都没有这个函数了,因此在1.4.2中将这个函数复制到了ajaxFileUpload.js中,问题解决
handleError: function( s, xhr, status, e ) {
// If a local callback was specified, fire it
if ( s.error ) {
s.error.call( s.context || s, xhr, status, e );
}
// Fire the global callback
if ( s.global ) {
(s.context ? jQuery(s.context) : jQuery.event).trigger( "ajaxError", [xhr, s, e] );
}
},
问题2:一直得到error ,无法执行指定的success方法。通过追踪ajaxFileUpload的执行过程发现,在调用它自身的uploadHttpData函数时,当执行if(type=="json") eval("data = "+data);
会抛出异常,导致在处理异常的时候将status = "error" 因此一直执行error方法。
上网查询,得知eval函数是用来执行一段js代码,而并不是如我所想的反解json串
eval("data = "+data);的意思是 将data 赋值给 data参数 ,但是当我返回给页面的是一个简单的字符串,比如"OK" ,时,这样写就抛出异常。最后改为 eval("data = \" "+data+" \" ");即将返回的数据用双引号引起来当作字符串,然后赋给 data 。终于成功了。。。
@RequestMapping(value = "/saveorupdate.jhtml") @ResponseBody public synchronized String saveOrUpdate(HttpServletRequest request) throws IOException { DynamicParams params = new DynamicParams(request); String projectId = request.getParameter("projectId"); String name = request.getParameter("name"); String type = request.getParameter("type"); params.put("projectId", projectId); params.put("name", name); params.put("type", type); MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request; MultipartFile file = null; if("1".equals(type)){ file = multipartRequest.getFile("file");// 获取上传文件名 }else{ file = multipartRequest.getFile("attachFile");// 获取上传文件名 } ProjectPic projectPic = params.convertToEntity(ProjectPic.class); projectPicManager.save(projectPic, file.getInputStream()); return successMsg(); }