下面给大家分享下基于ajax实现文件上传并显示进度条。在jsp部分,需要设计一个表单,form的属性添加 enctype="multipart/form-data",设计一个iframe,作为隐藏。form的target等于iframe的name;
在servlet部分:文件上传用的Commons-FileupLoad,需要两个Jar,commons-fileupload和commons-io,少了第二个会报出找不到类的异常;
第一个servlet处理上传,及把上传进度保存到session,第二个servlet处理ajax请求,回传session保存的进度值;
进度条:可以用ajax拿到回传的进度值,改变图片的width实现变化;
jsp代码:
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%><!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://.ul.servlet;import java.io.IOException;import java.io.PrintWriter;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.HttpSession;public class getProgressServlet extends HttpServlet { protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doPost(request, response); } protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("utf-8"); response.setCharacterEncoding("utf-8"); HttpSession sesson=request.getSession(); PrintWriter out=response.getWriter(); String str=(String)sesson.getAttribute("prog")+""; String res=(String)sesson.getAttribute("result"); String err=(String)sesson.getAttribute("error"); System.out.println(str+","+res+","+err); out.print(str+","+res+","+err); out.flush(); out.close(); }}效果图如下:
以上就是本文的全部内容,希望对大家有所帮助。