浅谈如何调用JSP读取数据库中图片并显示在页面上
记得当年当当网推出时用JSP读取数据库是从Oracle里读Blob图片，显示到页面上以后怎么都是个红叉子，无奈之下请教高人，答曰：这种事情一般用Servlet搞定比较好，因为JSP读取数据库终究会被翻译成JAVA代码然后编译成class，你的JSP难免出现一些格式转换什么的代码，一旦污染到读出来的image，则红叉子在所难免了。细想之下顿觉言之有理，Google之。果然发现很多朋友遇到过此问题，遂查之～，见有人说去掉全部空格就OK了，想想也对，就马上给代码净身（可怜我里缩外进的完美代码格式）～～
然后代码成了这副模样： <%@ page import="java.awt.image.BufferedImage"%>
<%@ page import="java.io.BufferedInputStream"%>
<%@ page import="java.io.IOException"%>
<%@ page import="java.sql.Connection"%>
<%@ page import="java.sql.ResultSet"%>
<%@ page import="java.sql.Statement"%>
<%@ page import="java.sql.Blob"%>
<%@ page import="oracle.sql.BLOB"%>
<%@ page import="javax.naming.InitialContext"%>
<%@ page import="javax.imageio.ImageIO"%>
<%@ page import="javax.sql.DataSource"%>
<%@ page import="javax.servlet.ServletOutputStream"%>
<%@ page import="com.sun.image.codec.jpeg.JPEGCodec"%>
<%@ page import="com.sun.image.codec.jpeg.JPEGImageEncoder"%>
<%InitialContext ic=new InitialContext();
DataSource ds=(DataSource)ic.lookup("DSNAME");
Connection conn=null;
conn =ds.getConnection);
Statement stmt=null;BufferedInputStream inputimage=null;
stmt=conn.createStatement();
boolean defaultCommit=conn.getAutoCommit();
conn.setAutoCommit(false);
String photoId =request.getParameter("photo_id");
try{
ResultSet rs=stmt.executeQuery("SELECT * FROM TABLENAME WHERE sys_id='"+photoId+"'");
if(rs.next()){Blob blob=(Blob)rs.getBlob("photo");
long size=blob.length();
byte[] bs=blob.getBytes(1,(int)size);
response.setContentType("image/jpeg;charset=GB2312");
response.setHeader("Content-Transfer-Encoding","base64");
OutputStream out1=response.getOutputStream();
BufferedOutputStream bos=null;
bos=new BufferedOutputStream(out1);
bos.write(bs,0,bs.length);bos.close();
rs.close();
}
else
{
rs.close();
}}
finally{
conn.close();
}%> 然后运行之～～，呵呵，调用JSP读取数据库中图片并显示在页面上就这样出来了～～～
from:http://go.cxweb.com.cn/s0uj4
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