用JSP实现文件上传功能

UploadExample.jsp

<%@ page contentType="text/html;charset=gb2312"%>

上传文件程序应用示例

<%-- 类型enctype用multipart/form-data，这样可以把文件中的数据作为流式数据上传，不管是什么文件类型，均可上传。--%>

请选择要上传的文件

doUpload.jsp

<%@ page contentType="text/html; charset=GBK" %>

<%@ page import="java.io.*"%>

<%@ page import="java.util.*"%>

<%@ page import="javax.servlet.*"%>

<%@ page import="javax.servlet.http.*"%>

<%

//定义上载文件的最大字节

int MAX_SIZE = 102400 * 102400;

// 创建根路径的保存变量

String rootPath;

//声明文件读入类

DataInputStream in = null;

FileOutputStream fileOut = null;

//取得客户端的网络地址

String remoteAddr = request.getRemoteAddr();

//获得服务器的名字

String serverName = request.getServerName();

//取得互联网程序的绝对地址

String realPath = request.getRealPath(serverName);

realPath = realPath.substring(0,stIndexOf("\\"));

//创建文件的保存目录

rootPath = realPath + "\\upload\\";

//取得客户端上传的数据类型

String contentType = request.getContentType();

try{

if(contentType.indexOf("multipart/form-data") >= 0){

//读入上传的数据

in = new DataInputStream(request.getInputStream());

int formDataLength = request.getContentLength();

if(formDataLength > MAX_SIZE){

out.println("

上传的文件字节数不可以超过" + MAX_SIZE + "

"); return;

}

//保存上传文件的数据

byte dataBytes[] = new byte[formDataLength];

int byteRead = 0;

int totalBytesRead = 0;

//上传的数据保存在byte数组

while(totalBytesRead < formDataLength){

byteRead = in.read(dataBytes,totalBytesRead,formDataLength); totalBytesRead += byteRead;

}

//根据byte数组创建字符串

String file = new String(dataBytes);

//out.println(file);

//取得上传的数据的文件名

String saveFile = file.substring(file.indexOf("filename=\"") + 10);

saveFile = saveFile.substring(0,saveFile.indexOf("\n"));

saveFile = saveFile.substring(stIndexOf("\\") + 1,saveFile.indexOf("\"")); int lastIndex = stIndexOf("=");

//取得数据的分隔字符串

String boundary = contentType.substring(lastIndex + 1,contentType.length());

//创建保存路径的文件名

String fileName = rootPath + saveFile;

//out.print(fileName);

int pos;

pos = file.indexOf("filename=\"");

pos = file.indexOf("\n",pos) + 1;

pos = file.indexOf("\n",pos) + 1;

pos = file.indexOf("\n",pos) + 1;

int boundaryLocation = file.indexOf(boundary,pos) - 4;

//out.println(boundaryLocation);

//取得文件数据的开始的位置

int startPos = ((file.substring(0,pos)).getBytes()).length;