小程序文件上传uploadFile

前台代码:

bindPhoto(e) {

var that = this;

wx.chooseImage({

count: 1,

sizeType: ['original','compressed'],// 指定原图或者压缩图

sourceType: ['album', 'camera'], // 指定图片来源

success: function (res) {

var tempFilePaths = res.tempFilePaths;

wx.uploadFile({

url: 'http://192.168.31.111:8007/goods/wx_upload.do',

filePath: tempFilePaths[0],

name: 'file',

header: { "Content-Type": "multipart/form-data" },

formData:{

'session_token': token

},

success:function(res){

var cur_data = res.data;

console.log(cur_data.fileName);

 

},

fail: function (res) {

console.log('上传失败');

}

})

}

})

},

后台代码

/*微信小程序上传图片测试*/
@RequestMapping("wx_upload.do")
public void wx_upload(HttpServletRequest request, HttpServletResponse response) throws Exception {
    request.setCharacterEncoding("utf-8");  //设置编码
//获得磁盘文件条目工厂
DiskFileItemFactory factory = new DiskFileItemFactory();
    ServletFileUpload upload = new ServletFileUpload(factory);
    String fileId = null;
    String json = "{"success":false,"fileName":"" + fileId + ""}";
    String pathUrl = FSDefaultMgr.E_DEFAULT.getDefaultUploadPathUrl();//获取图片服务器路径
InputStream inStream = null;
    try {
        //可以上传多个文件
List<FileItem> list = (List<FileItem>)upload.parseRequest(request);
        for(FileItem item : list){
            //获取表单的属性名字
String name = item.getFieldName();
            //如果获取的 表单信息是普通的 文本 信息
if(item.isFormField()){
                //获取用户具体输入的字符串 ，名字起得挺好，因为表单提交过来的是 字符串类型的
String value = item.getString() ;
                request.setAttribute(name, value);
            }else {
                //获取路径名
String filename = item.getName();
                request.setAttribute(name, filename);
                inStream = item.getInputStream() ;
            }
        }
        ByteArrayOutputStream swapStream = new ByteArrayOutputStream();
        byte[] buff = new byte[100];
        int rc = 0;
        while ((rc = inStream.read(buff, 0, 100)) > 0) {
            swapStream.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

1. <bean id="multipartResolver"  
2.         class="org.springframework.web.multipart.commons.CommonsMultipartResolver">  
3.         <property name="defaultEncoding" value="UTF-8" />  
4.   
5.         <property name="maxUploadSize" value="2000000000" />  
6.     </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

1. <!--   
2.     <bean id="multipartResolver"  
3.         class="org.springframework.web.multipart.commons.CommonsMultipartResolver">  
4.         <property name="defaultEncoding" value="UTF-8" />  
5.   
6.         <property name="maxUploadSize" value="2000000000" />  
7.     </bean>  
8.      -->  

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 +"	" + arg1 +"	" + 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)

1. <bean id="multipartResolver"  
2.         class="com.lwp.spring.ext.CommonsMultipartResolverExt">  
3.         <property name="defaultEncoding" value="UTF-8" />  
4.         <property name="maxUploadSize" value="2000000000" />  
5.     </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.