在jsp中通过I/O流方式读取图片并展示到页面

来源：互联网发布：小米笔记本装mac系统编辑：程序博客网时间：2024/05/20 15:11

之前在做一个项目时用到了图片上传并立即展示到页面浏览，而且图片存放在硬盘上的一个文件夹中而非在工程与数据库中，这就会出现一个问题，如果不是在开发程序环境中访问图片页面，则会出现图片不能展示情况，原因很明显，就是外部无法访问到服务器硬盘上的图片。所以这时就需要用到i/o流读取图片并展示，以下是具体步骤：

1.图片展示页面showImg.jsp

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html>  <head>    <base href="<%=basePath%>">        <title>i/o流读取图片</title>    <meta http-equiv="pragma" content="no-cache"><meta http-equiv="cache-control" content="no-cache"><meta http-equiv="expires" content="0">    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"><meta http-equiv="description" content="This is my page"><script src="local/communication/static/jquery.min.js" charset="utf-8"></script><!--<link rel="stylesheet" type="text/css" href="styles.css">-->  </head>    <body>  <div>     <img id="viewImg2" src="local/communication/db/img.jsp?flag=zheng" style="height:90px;width:200px;" >  </div>      </body></html>

2.通过jsp页面服务读取图片，imp.jsp代码：

<%@ page language="java" import="java.util.*,java.util.Map.Entry,java.text.SimpleDateFormat,java.util.Date,net.sf.json.JSONArray,net.sf.json.JSONObject,java.net.URLEncoder,java.net.URLDecoder" pageEncoding="utf-8"%><%@page import="java.io.FileInputStream"%><%@page import="java.io.BufferedOutputStream"%><%@page import="java.io.InputStream"%><%@page import="java.io.BufferedInputStream"%><%@page import="java.io.OutputStream,java.io.FileOutputStream,java.io.IOException,java.io.FileInputStream,java.io.PrintWriter," %><%request.setCharacterEncoding("UTF-8");response.setContentType("image/png");response.setHeader("Content-Disposition","attachment;Filename=test.png");BufferedOutputStream bos = null;InputStream fis = null;BufferedInputStream bis = null;String flag=request.getParameter("flag")==null?"":request.getParameter("flag");try{String tPath="D://img/11.jsp";bos = new BufferedOutputStream(response.getOutputStream());fis = new FileInputStream(tPath);bis = new BufferedInputStream(fis);byte[] buff = new byte[2048];int bytesRead;while (-1 != (bytesRead = bis.read(buff, 0, buff.length))){bos.write(buff, 0, bytesRead);}bos.flush();}catch(Exception e){}finally{if(bos!=null){bos.close();}if(bis!=null){bis.close();}if(fis!=null){fis.close();}}out.clear();out = pageContext.pushBody();%>

阅读全文

0 0