part（）上传图片

<form action="up.do" method="post" enctype="multipart/form-data">
    <input type="file" name="file">
    <input type="submit" value="submit">    
    </form>

@WebServlet("/up.do") @MultipartConfig
public class Up extends HttpServlet {
    public void service(ServletRequest request, ServletResponse response)
            throws ServletException, IOException {
        HttpServletRequest req=(HttpServletRequest)request;
        req.setCharacterEncoding("utf-8");
        Part part=req.getPart("file");//获取指定表单文件
        part.write("c:/web811.jpg");//将文件写入指定路径
    }
}