SpringMVC檔案上傳和下載(基本步驟)
阿新 • • 發佈:2021-01-24
檔案上傳
- 引入jar包
<dependency> <groupId>commons-fileupload</groupId> <artifactId>commons-fileupload</artifactId> <version>1.3.3</version> </dependency>
- 配置bean:multipartResolver
【注意!!!這個bena的id必須為:multipartResolver , 否則上傳檔案會報400的錯誤!】<!--檔案上傳配置-->
- Controller
/** 採用file.Transto 來儲存上傳的檔案 */ @RequestMapping("/upload2") public String fileUpload2(@RequestParam("file"
檔案下載
檔案下載步驟:
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設定 response 響應頭
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讀取檔案 – InputStream
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寫出檔案 – OutputStream
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執行操作
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關閉流 (先開後關)
@RequestMapping(value="/download") public String downloads(HttpServletResponse response ,HttpServletRequest request) throws Exception{ //要下載的圖片地址 String path = request.getServletContext().getRealPath("/upload"); String fileName = "基礎語法.jpg"; //1、設定response 響應頭 response.reset(); //設定頁面不快取,清空buffer response.setCharacterEncoding("UTF-8"); //字元編碼 response.setContentType("multipart/form-data"); //二進位制傳輸資料 //設定響應頭 response.setHeader("Content-Disposition", "attachment;fileName="+URLEncoder.encode(fileName, "UTF-8")); File file = new File(path,fileName); //2、 讀取檔案--輸入流 InputStream input=new FileInputStream(file); //3、 寫出檔案--輸出流 OutputStream out = response.getOutputStream(); byte[] buff =new byte[1024]; int index=0; //4、執行 寫出操作 while((index= input.read(buff))!= -1){ out.write(buff, 0, index); out.flush(); } out.close(); input.close(); return null; }