使用到的jar文件:commons-fileupload-1.3.jar,commons-io-2.4.jar
jsp頁面:
<%@ 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>My JSP 'index.jsp' starting page</title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<form action="<%=basePath%>FileUploadServlet" method="post" enctype="multipart/form-data" target="hidden_iframe">
<input type="file" name="file" id="uploadfile" /><span style="color:red;" id="msg"></span><br/>
<input type="submit" value="submit" />
<iframe name="hidden_iframe" style="display:none;"></iframe>
</form>
</body>
<script type="text/javascript">
function callback(msg){
document.getElementById("uploadfile").outerHTML = document.getElementById("uploadfile").outerHTML;
document.getElementById("msg").innerHTML = msg;
alert(msg);
}
</script>
</html>
提交的頁面在iframe中打開,利用隱藏的iframe實現無刷新上傳文件,並不是真正的動態無刷新。
Servlet文件:
package com.upload;
import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Iterator;
import java.util.List;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
public class FileUploadServlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
this.doPost(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
boolean isMultipart = ServletFileUpload.isMultipartContent(request);
int flag = 0;//0 上傳失敗 1上傳成功
if(isMultipart){
DiskFileItemFactory factory = new DiskFileItemFactory();
factory.setSizeThreshold(5*1024);
ServletContext servletContext = this.getServletConfig().getServletContext();
File repository = (File) servletContext.getAttribute("javax.servlet.context.tempdir");
factory.setRepository(repository);
ServletFileUpload upload = new ServletFileUpload(factory);
upload.setSizeMax(5*1024*1024);
upload.setHeaderEncoding("utf-8");
String uploadPath = servletContext.getRealPath("/")+File.separator+"upload";
try {
List<FileItem> items = upload.parseRequest(request);
Iterator<FileItem> iter = items.iterator();
while (iter.hasNext()) {
FileItem item = iter.next();
String filedName = item.getFieldName();//獲取field的name屬性
if (!item.isFormField()) {
if(!"".equals(filedName.trim())){
File file = new File(uploadPath, item.getName());
item.write(file);
item.delete();
flag = 1;
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
response.setContentType("text/html");
response.setCharacterEncoding("utf-8");
PrintWriter out = response.getWriter();
if(flag == 1){
out.print("<script>parent.callback('上傳成功!')</script>");
}else{
out.print("<script>parent.callback('上傳失敗!')</script>");
}
}
}