Vue+axios+Servlet 中提交表单数据(含上传图片)超详版！！！

package com.web.admin;
 
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;
 
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
 
import com.service.admin.AdminTsuService;
 
/**
 * Servlet implementation class Uploadfile
 */
@WebServlet("/uploadfile")
public class Uploadfile extends HttpServlet {
    private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public Uploadfile() {
        super();
        // TODO Auto-generated constructor stub
    }
 
    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        //response.getWriter().append("Served at: ").append(request.getContextPath());
 
 
    }
 
    /**
     * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
      // TODO Auto-generated method stub
      doGet(request, response);
      //设置编码方式
      request.setCharacterEncoding("utf-8");
      response.setCharacterEncoding("gb2312");
      
      
      //设置输出
      PrintWriter outprint = response.getWriter();
      //Enumeration files = multipartRequest.getFileNames();
      //设置文件目录
      String webroot = this.getServletContext().getRealPath("/");
      File temppath = new File(webroot + "fileuploadtemp");
      String dir = webroot+ File.separator + "upload";
      File path = new File(webroot+ File.separator + "upload");
      if (!temppath.exists()) {
          temppath.mkdirs();
      }
      if (!path.exists()) {
          path.mkdirs();
      }
 
      //设置文件类型(可加)
      String[] type= new String[]{".jpg",".png",".jpeg",".gif",".bmp"};
 
      //创建文件项工厂
      DiskFileItemFactory factory = new DiskFileItemFactory(1024 * 1024,temppath);
      ServletFileUpload upload = new ServletFileUpload(factory);
      upload.setFileSizeMax(1024 * 1024 * 10);
      try {
          List<FileItem> fileItems = upload.parseRequest(request);
          Iterator<FileItem> it = fileItems.iterator();
          String newFimeName=null;
          String tstitle1=null;
          String tscontent1=null;
          //String tstitle2=null;
          //String tscontent2=null;
          //String name1 = "tstitle";
          //String content1 = "tscontent";
          // int count = 0;
 
          //遍历request file
          while (it.hasNext()) {
              FileItem fi = it.next();
              
              //判断该表单是否为普通表单类型
              if (fi.isFormField()) {
                  String nameString = fi.getFieldName();
                  switch(nameString)
                  {
                     case "tstitle" :
                        //解决转换字节流乱码问题
                        tstitle1 =  new String(fi.getString().getBytes("ISO8859_1"),"utf-8");
                        
                        System.out.println(tstitle1); 
                        break;
                     case "tscontent" :
                         tscontent1 =  new String(fi.getString().getBytes("ISO8859_1"),"utf-8");
                         System.out.println(tscontent1); 
                         break; 
                     default :
                        System.out.println("未知等级");
                  
                }
                  
                  //System.out.println("----"+nameString+"-------");
                  //System.out.println("----"+conString+"-------"); 
              } else {
                  InputStream in = fi.getInputStream();
                  String name = fi.getName();//获得文件原名
 
                  //得到文件后缀名
                  int index = name.lastIndexOf(".");
                  String endWith = name.substring(index);
 
                  //判断是否符合类型
                  boolean TypeExists = Arrays.asList(type).contains(endWith);
                  if (!TypeExists) {
                      outprint.print("<script>\n" +
                              "alert(\"文件类型错误，只允许jpg,png,jpeg,gif\");location=\"fileup.html\";\n" +
                              "</script>");
                      return;
                      }
 
                      newFimeName = System.currentTimeMillis() + endWith;//新文件名
 
                      //创建上传文件
                      FileOutputStream out = new FileOutputStream(new File(
                              dir + "/" + newFimeName));
 
                      byte buffer[] = new byte[1024];
                      int len = 0;
                      while ((len = in.read(buffer)) > 0) {
                          out.write(buffer, 0, len);//写入大小
                      }
                      
                      in.close();
                      out.close();
                      fi.delete();
                      
                    //  outprint.print("上传成功");
                  }
              }
          
          AdminTsuService tsuService = new AdminTsuService();
          String tsu=tsuService.addone(tstitle1, tscontent1,newFimeName);//调用service层方法
          outprint.println(tsu);
          outprint.flush();//清除缓冲区的数据
          outprint.close();//关闭流     
          } catch(FileUploadException e){
              response.getWriter().write(e.toString());
          }
    }
}

    public String addone(String tstitle,String tscontent,String tspicture) {
        int add=tsu.addone(tstitle, tscontent,tspicture);
        return JSON.toJSON(add).toString();
    }

    public int addone(String tstitle,String tscontent,String tspicture) {        
        String sql="insert into tsu(tstitle,tscontent,tspicture) values (?,?,?)";
        int i = DH.update(sql, new String[] {tstitle,tscontent,tspicture});
        return i;
    }