前置码：
bindphoto(e ) { var that=this； wx.chooseimage((count:1，sizetype:('original '，' compressed']'] ' )、//原图或压缩图中的source type : (' ) 指定' compressed ' )的wx.uploadfile (URL : ' http://192.168.31.11133608007/goods/wx _ upload.do '， file path : tempfile paths [0] header : { ' content-type ' : ' multipart/form-data ' }，formdata 3360 { ' sesision } 、故障：功能(RES ) { console.log (“上传失败”)； }}}}}，后台代码/*微信小程序为图像测试*/@requestmapping(wx_upload.do ) publicvoidwx_upload ) httpservletrequestrequestrequest htpservletresponsereresponse (tereresponse ) //编码设置//磁盘文件条目工厂diskfileitemfactoryfactory=newdiskfileitemfactory (； servletfileuploadupload=newservletfileupload (factory； 字符串文件id=null； string JSON=' {' success' : false，'fileName':'' fileId ''}； stringpathurl=fsdefaultmgr.e _ default.getdefaultuploadpathurl (； //图像服务器路径inputstream instream=可以上传获取null的try { //多个文件的listfileitemlist=(listfileitem ) upload.parserequest ) for(fileitemitem:list(/获取表单的属性名称String name=item.getFieldName ) )； //在取得的表格信息取得通常的文本信息if(item.isformfield () /用户具体输入的字符串的情况下，表格发送字符串型的String value=item.getString ) ) request.setattribute(name，value )； }else { //路径名String filename=item.getName (； request.setattribute(name，filename )； inStream=item.getInputStream (； } bytearrayoutputstreamswapstream=newbytearrayoutputstream (； byte[] buff=new byte[100]； int rc=0； while((RC=instream.read ) buff，0，100 ) )0) { swap
Stream.write(buff, 0, rc); } byte[] bytes = swapStream.toByteArray(); fileId = FastDFSClient.uploadFile(bytes, "20161545454.png", null); if (fileId != null) { json = "{"success":true,"pathUrl":"" + pathUrl + "","fileName":"" + fileId + ""}"; } response.getWriter().write(json); response.getWriter().flush(); response.getWriter().close(); }catch (Exception e) { e.printStackTrace(); }}当使用的是springMVC框架时： SpringMVC中servletFileUpload.parseRequest(request)解析为空获取不到数据问题 原因分析
首先我们来看下Spring mvc 中文件上传的配置
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> <property name="defaultEncoding" value="UTF-8" /> <property name="maxUploadSize" value="2000000000" /> </bean>
再来看看Controller中使用
public void upload2(HttpServletRequest request) { // 转型为MultipartHttpRequest try { MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request; List<MultipartFile> fileList = multipartRequest.getFiles("file"); for (MultipartFile mf : fileList) { if(!mf.isEmpty()){ } } } catch (Exception e) { e.printStackTrace(); } }
方式二
public String upload(HttpServletRequest request, @RequestParam(value = "file") MultipartFile[] files) { try { for (MultipartFile mf : files) { if(!mf.isEmpty()){ } } } catch (Exception e) { e.printStackTrace(); } return "upload"; } 这里springMVC 都为我们封装好成自己的文件对象了,转换的过程就在我们所配置的CommonsMultipartResolver这个转换器里面下面再来看看它的源码
他的转换器里面就是调用common-fileupload的方式解析,然后再使用parseFileItems()方法封装成自己的文件对象 .
List<FileItem> fileItems = ((ServletFileUpload) fileUpload).parseRequest(request);
大家应该发现了上面的这句代码,已经使用过fileUpload解析过request了,你在Controller里面接收到的request都已经是解析过的,你再次使用upload进行解析获取到的肯定是空,这个就是问题的所在(大家可以在servlet里面实验,看看第二次解析后能不能获取到数据,当然是不能的)
解决方案
1)删除Spring MVC文件上传配置
<!-- <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> <property name="defaultEncoding" value="UTF-8" /> <property name="maxUploadSize" value="2000000000" /> </bean> --> 在控制器里面自己完成request的解析(当然上面spring MVC提供的两种方法是不能用的,所有上传的地方都需要自己做处理)public void upload3(HttpServletRequest request) { DiskFileItemFactory factory = new DiskFileItemFactory(); ServletFileUpload upload = new ServletFileUpload(factory); try { List<FileItem> list = upload.parseRequest(request); for(FileItem item : list){ if(item.isFormField()){ }else{ //item.write(new File("")); } } } catch (FileUploadException e) { e.printStackTrace(); } }
2)如果是需要使用的ProgressListener监听器我们可以重写 CommonsMultipartResolver的parseRequest方法
package com.lwp.spring.ext; import java.util.List; import javax.servlet.http.HttpServletRequest; import org.apache.commons.fileupload.FileItem; import org.apache.commons.fileupload.FileUpload; import org.apache.commons.fileupload.FileUploadBase; import org.apache.commons.fileupload.FileUploadException; import org.apache.commons.fileupload.servlet.ServletFileUpload; import org.springframework.web.multipart.MaxUploadSizeExceededException; import org.springframework.web.multipart.MultipartException; import org.springframework.web.multipart.commons.CommonsMultipartResolver; import com.lwp.listener.FileUploadListener; public class CommonsMultipartResolverExt extends CommonsMultipartResolver { @Override protected MultipartParsingResult parseRequest(HttpServletRequest request) throws MultipartException { FileUploadListener listener = new FileUploadListener(); String encoding = determineEncoding(request); FileUpload fileUpload = prepareFileUpload(encoding); fileUpload.setProgressListener(listener); try { List<FileItem> fileItems = ((ServletFileUpload) fileUpload).parseRequest(request); return parseFileItems(fileItems, encoding); } catch (FileUploadBase.SizeLimitExceededException ex) { throw new MaxUploadSizeExceededException(fileUpload.getSizeMax(), ex); } catch (FileUploadException ex) { throw new MultipartException("Could not parse multipart servlet request", ex); } } }
监听器方法
import org.apache.commons.fileupload.ProgressListener; public class FileUploadListener implements ProgressListener { @Override public void update(long arg0, long arg1, int arg2) { //arg0 已经上传多少字节 //arg1 一共多少字节 //arg2 正在上传第几个文件 System.out.println(arg0 +"t" + arg1 +"t" + arg2); } }
配置文件改为我们自己的(这种方式的缺陷是,所有文件上传都需要使用到Listener)
<bean id="multipartResolver" class="com.lwp.spring.ext.CommonsMultipartResolverExt"> <property name="defaultEncoding" value="UTF-8" /> <property name="maxUploadSize" value="2000000000" /> </bean>注: 综上所述,如果只是普通的文件上传spring MVC 完全可以完成,如果需要使用进度条的listener前段可以使用假的进度条或者是上面的两种方式.