web---資源的下載及中文亂碼問題
阿新 • • 發佈：2019-04-26
cte 問題 處理 javax except 找不到 註冊 exce lan
1、html網頁，超鏈接交由Servlet處理
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <h1>實現文件的下載功能</h1> <a href="ImgServlet?filename=a.jpg">aa</a><br> <a href="ImgServlet?filename=b.jpg">bb </a><br> <a href="ImgServlet?filename=圖片.png">圖片</a><br> </body> </body> </html>
2.web.xml----Servlet的註冊
<servlet>
<servlet-name>DownLoadImgServlet</servlet-name>。--1
<servlet-class>nee.DownLoadImgServlet</servlet-class
--1 2 處名字必須相同
3.Servlet的實現
package nee; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.net.URLEncoder; @WebServlet(name= "DownLoadImgServlet") public class DownLoadImgServlet extends HttpServlet { protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doGet(request,response); } protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { /* 用字節輸出流向文件寫資源 資源需要從輸入流中讀入 輸入流為圖片構成的輸入流 */ String filename=request.getParameter("filename"); //解決中文找不到資源路徑的問題 filename = new String(filename.getBytes("ISO-8859-1"),"UTF-8"); //將文件轉化為輸入流 InputStream is=getServletContext().getResourceAsStream("download/"+filename); //解決文件名不顯示中文的問題 filename=URLEncoder.encode(filename,"UTF-8"); //聲明這是一個下載的文件 response.setHeader("Content-Disposition","attachment;filename="+filename); OutputStream os=response.getOutputStream(); int len=0; byte[] buffer = new byte[1024]; while ((len=is.read(buffer) )!= -1){ os.write(buffer,0,len); } } }
web---資源的下載及中文亂碼問題