使用smartUpload上传文件

朱雀 2023-10-05 09:53 8阅读 0赞

### 使用jsp，servlet，smartUpload完成上传文件 ###

### 如何使用smartUpload完成文件上传操作？ ###

描述：  
表单提交设置格式（文件上传固定配置）：  
`<form action="SmartUploadSvt" enctype="multipart/form-data" method="post">`

servlet中，我们使用smartUpload完成上传，限制上传文件格式大小等，并且不符合上传标准不能上传，弹出提示框。  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1poYVpoYV9fSHVp_size_16_color_FFFFFF_t_70_pic_center]

注意：  
smartUpload.upoad()表示上传准备工作

smartUpload.save(" ")或者su.getFiles().getFile(0).saveAs()才是上传到指定目录

**完整代码**：  
**jsp**：

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
    <html>
      <head> 
        <title>SmartUpload</title>
      </head>
      <body>
        <form action="SmartUploadSvt" enctype="multipart/form-data" method="post">
               请选择文件：<input type="file" name="myfile"/><br><br>
        <input type="submit" value="上传"/>
        </form>
      </body>
    </html>

**servlet**：

package svt;
    
    import java.io.IOException;
    import java.io.PrintWriter;
    import java.util.UUID;
    
    import javax.servlet.ServletException;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import javax.servlet.jsp.JspFactory;
    import javax.servlet.jsp.PageContext;
    
    import com.jspsmart.upload.SmartUpload;
    import com.jspsmart.upload.SmartUploadException;
    
    public class SmartUploadSvt extends HttpServlet {
        
    
    	public void doGet(HttpServletRequest request, HttpServletResponse response)
    			throws ServletException, IOException {
        
    		request.setCharacterEncoding("utf-8");
    		response.setCharacterEncoding("utf-8");
    		response.setContentType("text/html; charset=UTF-8");
    		SmartUpload su = new SmartUpload();/* 创建SmartUpload对象 */
    		PageContext pageContext = JspFactory
    				.getDefaultFactory()
    				.getPageContext(this, request, response, null, true, 8019, true);
    		su.initialize(pageContext);/* 初始化SmartUpload对象 */
    		su.setCharset("utf-8");/* 设定上传字符集 */
    		su.setAllowedFilesList("txt,jpg,png");/*限制文件格式类型*/
    		su.setMaxFileSize(3 * 1024 * 1024);/* 限制上传文件大小3m */
    		boolean flag = false;/*初始化上传审核不通过为false*/
    		try {
        
    			su.upload();/* 上传准备 */
    			flag = true;/* 准备完成，标记flag */
    		}catch(Exception e){
        
    		}
    
    		/* 判定flag，如果为true则上传准备完成，否则不符合上传规则 */
    		if (flag) {
        			
    			String uuid = UUID.randomUUID().toString().replace("-", "");/*创建唯一识别uuid*/
    			String ext=su.getFiles().getFile(0).getFileExt();/*获取文件后缀*/
    			String fileName=uuid+"."+ext;/*重命名文件名（uuid+后缀）*/
    			try {
        
    				su.getFiles().getFile(0).saveAs("\\smartUploadFile\\"+fileName);/* 上传到指定路径 */
    			} catch (SmartUploadException e) {
        
    				e.printStackTrace();
    			}
    			request.setAttribute("fileName", fileName);
    			request.getRequestDispatcher("suOK.jsp").forward(request, response);
    		} else {
        
    			PrintWriter out = response.getWriter();/* 获取out输出内置对象 */
    			out.println("<script type='text/javascript'>alert('上传文件类型或大小不合要求，请重新尝试！');location='smartUpload.jsp';</script>");
    		}
    
    	}
    
    	public void doPost(HttpServletRequest request, HttpServletResponse response)
    			throws ServletException, IOException {
        
    		doGet(request, response);
    	}
    
    }

**上传成功jsp**：

<%@ page language="java" contentType="text/html; charset=utf-8"
        pageEncoding="utf-8"%>
    <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    <html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
    <title>smartUpload上传文件成功</title>
    </head>
    <body>
    已上传文件：<a href="smartUploadFile/${fileName }">${
        fileName }</a>
    </body>
    </html>

**补充**：

### 使用smartUpload获取不到表单信息内容怎么办？ ###

解决方案：  
在smartUpload.upoad()下面添加以下代码，smartUpload封装了request，必须通过调用指定方法才能使用request

....
    smartUpload.upoad();
    String messagae = SmartUpload.getRequest().getParameter("ms");
    System.out.println("描述："+messagae);

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1poYVpoYV9fSHVp_size_16_color_FFFFFF_t_70_pic_center]: https://img-blog.csdnimg.cn/20200910194026237.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1poYVpoYV9fSHVp,size_16,color_FFFFFF,t_70#pic_center