web图片上传功能

Love The Way You Lie 2023-06-05 12:31 29阅读 0赞

//首先对请求进行解析，判断是不是一个上传文件的表单请求
    boolean isMultipart = ServletFileUpload.isMultipartContent(request);
    if (isMultipart) {
    	try {
    		//1.实例化缓冲区
    		DiskFileItemFactory factory = new DiskFileItemFactory();
    		//2.获取对文件操作的对象
    		ServletFileUpload upload = new ServletFileUpload(factory);
    		//设置上传数据时的默认字符集
    		upload.setHeaderEncoding("UTF-8");
    		//设置上传文件大小
    		upload.setSizeMax(10 * 1024 * 1024);
    
    		//获取所有表单项
    		List<FileItem> fileItems = upload.parseRequest(request);
    		
    		Iterator<FileItem> iter = fileItems.iterator();
    
    		// 依次处理每个表单域
    		while (iter.hasNext()) {
    			FileItem item = (FileItem) iter.next();
    
    			if (!item.isFormField()) {
    				// 如果item是上传文件
    				// 获得文件名及路径
    				String fileName = item.getName();
    
    				if (fileName != null && fileName.indexOf(".") != -1) {
    					//设置上传文件的新文件名，UUID
    					String fileNewName = UUID.randomUUID().toString().replace("-","")
    							+ "."
    							+ fileName.substring(fileName.indexOf(".") + 1);
    					//把文件保存在服务器上本web应用目录下
    					File fullFile = new File(getServletContext()  
    							.getRealPath("/images/photo/"), fileNewName);
    					
    					//写文件
    					item.write(fullFile);
    					
    				
    					
    					request.setAttribute("imagePath", "images/photo/"+fileNewName);
    					request.getRequestDispatcher("upload.jsp").forward(request, response);
    			} else {
    				}
    				item.delete();
    			}
    		}
    	} catch (Exception e) {
    		e.printStackTrace();
    	}
    }

小结：form表单的enctype 属性必须是 multipart/form-data” 注意post请求