Struts2实现文件上传和下载，多文件上传，限制文件大小，限制文件类型

文件上传使用的包：commons-upload-xx.jar

                                commons-io-xx.jar

一.实现文件上传：

1.在表单空间中添加enctype=”multipart/form-data”

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

2.创建Action:

           ①在action中添加属性

                private File xnamex;    //指定文件名，文件名必须与文件域的name属性名一样

                private String xnamexUploadContentType;  //文件类型

                private String xnamexFileName;   //文件名称

            ②重写execute或自定义方法：

                获取远程站点真正路径,指定文件保存路径：

                  String savePath= ServletActionContext.getServletContext.get(“/upload”);

                通过IO操作将文件写入保存文件夹

  1: package com.action;
  2: import java.io.File;
  3: import org.apache.commons.io.IOUtils;
  4: import org.apache.struts2.ServletActionContext;
  5: import com.opensymphony.xwork2.ActionSupport;
  6: 
  7: public class UploadAction extends ActionSupport {
  8:   private File upload;//上传的文件
  9:   private String uploadContentType;//文件类型
 10:   private String uploadFileName;//文件名
 11:   
 12:   public File getUpload() {
 13:     return upload;
 14:   }
 15:   public void setUpload(File upload) {
 16:     this.upload = upload;
 17:   }
 18:   public String getUploadContentType() {
 19:     return uploadContentType;
 20:   }
 21:   public void setUploadContentType(String uploadContentType) {
 22:     this.uploadContentType = uploadContentType;
 23:   }
 24:   public String getUploadFileName() {
 25:     return uploadFileName;
 26:   }
 27:   public void setUploadFileName(String uploadFileName) {
 28:     this.uploadFileName = uploadFileName;
 29:   }
 30:   @Override
 31:   public String execute() throws Exception {
 32:     String savaPath = ServletActionContext.getServletContext()
 33:         .getRealPath("/upload");
 34:     FileOutputStream fos=null;
 35:     FileInputStream fis=null;
 38:       fis=new FileInputStream(upload[i]);
 39:       fos=new FileOutputStream(savaPath+"\\"+uploadFileName[i]);
 44:       IOUtils.copy(fis, fos);
 45:       fis.close();
 46:       fos.flush();
 47:       fos.close();
 49:     return "success";
 50:   }
 52: }

3.在struts2.xml文件中配置：

<action name="upload" class="com.action.UploadAction">
      <result name="success">/uploadfile.jsp</result>
</action>

 

 

二.限制文件大小:

方法一：在struts2.xml文件中配置常量参数：

<constant name=”struts.multipart.maxSize” value=”50000” />

value值  为  byte

方法二：在action中引用系统定义的fileUpload拦截器,

              配置拦截器参数：<param name=”maximumSize”>50000</param>

三.限制文件类型:

 

在action中引用系统定义的fileUpload拦截器,

              配置拦截器参数：

<param name=”allowedTypes”>application/msword,·····</param>

tomcat中，在conf/web.xml中查找type

 

 

四.实现多个文件同时上传

①，将Action中属性改为数组：

               private File[]  xnamex;    //指定文件名

                private String[]  xnamexUploadContentType;  //文件类型

                private String[]  xnamexFileName;   //文件名称

②，在方法中添加数组遍历

 

五.在struts.xml中配置中配置保存路径

①.在action标签中添加参数配置

<param name=”path”>upload</param>   //指定文件夹名

②.修改文件上传Action：

添加属性：private String path;  //与配置文件中参数的name属性一致

更改保存路径：savaPath=ServletActionContext.getActionContext.get(“/”+path);

 

 

 

 

实现文件下载 （点击）

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