Form表单上传文件（type="file"）的使用

一，单个文件的上传

1.html/jsp页面

<%@ page language="java" contentType="text/html; charset=UTF-8"
  pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<%
  String path=request.getContextPath();
  request.setAttribute("path", path);
%>
</head>
<body>
<form action="${path}/FileSer" method="post" enctype="multipart/form-data">
  <table>
    <tr>
      <td>上传文件</td>
      <td>
        <input type="file" name="fileN" />
      </td>
    </tr>
    <tr>
      <td colspan="2">
        <input type="submit" />
        <input type="reset" />
      </td>
    </tr>
  </table>
  </form>
</body>
</html>

2.过滤器解决中文乱码问题

package com.ser;
import java.io.IOException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class Filter01 implements Filter
{
  @Override
  public void destroy()
  {
  }
  @Override
  public void doFilter(ServletRequest arg0, ServletResponse arg1,
      FilterChain arg2) throws IOException, ServletException
  {
    HttpServletRequest request= (HttpServletRequest)arg0;
    HttpServletResponse response=(HttpServletResponse)arg1;
    request.setCharacterEncoding("utf-8");
    response.setCharacterEncoding("utf-8");
    response.setContentType("text/html charset=utf-8");
    arg2.doFilter(request, response);
  }
  @Override
  public void init(FilterConfig arg0) throws ServletException
  {
  }
}

3.处理html/jsp

package com.ser;
import java.io.File;
import java.io.IOException;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.annotation.MultipartConfig;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.Part;
/**
 * Servlet implementation class FileSer
 */
@WebServlet("/FileSer")
@MultipartConfig(location="e://uploadFile",
    fileSizeThreshold=1024*1024*1000,
    maxFileSize=1024*1024*1000,
    maxRequestSize=1024*1024*1024
    )
public class FileSer extends HttpServlet {
  private static final long serialVersionUID = 1L;
  private static final String location="e://uploadFile";
  /**
   * @see HttpServlet#HttpServlet()
   */
  public FileSer() {
  }
  @Override
  public void init(ServletConfig config) throws ServletException
  {
    File file =new File("e://uploadFile");
    if(!file.exists()&& !file.isDirectory())
    {
      file.mkdir();
    }
  }
  /**
   * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
  }
  /**
   * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
   */
  protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    Part part= request.getPart("fileN");
    String fileType=part.getContentType();
    String fileHeader=part.getHeader("content-disposition");
    //String fileName=part.getName();
    long size=part.getSize();
    System.out.println(part);
    System.out.println(fileType);
    System.out.println(fileHeader);
    //System.out.println(fileName);
    System.out.println(size);
    String filename=fileHeader.substring(fileHeader.indexOf("filename=")+10, fileHeader.lastIndexOf("\""));
    part.write(filename);
    response.getWriter().print(filename+"上传成功");
  }
}

总结

以上所述是小编给大家介绍的Form表单上传域（type="file"）的使用(上传文件)，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对我们网站的支持！