文件上傳
1）三個條件：
表單有file
post提交
enctype="multipart/form-data"
2)在Action中接收文件內容
File attach; (attach是file表單的name屬性)
String attachContentType; 文件類型
String attachFileName; 文件名稱
細節：
修改上傳大小
頁面：
<%@ page language="java" import="java.util.*" pageEncoding="utf-8" isELIgnored="false" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<body>
<h2>request</h2>
<table border="1">
<c:forEach items="${requestScope.request_list}" var="user">
<tr>
<td>${user}</td>
</tr>
</c:forEach>
</table>
<h2>session</h2>
<table border="1">
<c:forEach items="${sessionScope.session_list}" var="user">
<tr>
<td>${user}</td>
</tr>
</c:forEach>
</table>
<h2>context</h2>
<table border="1">
<c:forEach items="${applicationScope.context_list}" var="user">
<tr>
<td>${user}</td>
</tr>
</c:forEach>
</table>
</body>
</html>
struts2.xml的配置
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.5//EN"
"http://struts.apache.org/dtds/struts-2.5.dtd">
<struts>
<package name="upload" extends="struts-default" namespace="/">
<action name="upload" class="com.bin.action.UploadAction" method="upload">
<param name="savePath">e:/images/</param>
<result name="success">/index.jsp</result>
</action>
</package>
</struts>
action：
package com.bin.action;
import com.opensymphony.xwork2.ActionSupport;
import org.apache.commons.io.FileUtils;
import java.io.File;
import java.io.IOException;
public class UploadAction extends ActionSupport {
//接收上傳文件，名字來源於頁面的File的name屬性
public File attach;
//接收文件的類型
public String attachContentType;
//接收文件的名稱
public String attachFileName;
//接收描述
public String info;
public String savePath;
public String getSavePath() {
return savePath;
}
public void setSavePath(String savePath) {
this.savePath = savePath;
}
public File getAttach() {
return attach;
}
public void setAttach(File attach) {
this.attach = attach;
}
public String getAttachContentType() {
return attachContentType;
}
public void setAttachContentType(String attachContentType) {
this.attachContentType = attachContentType;
}
public String getAttachFileName() {
return attachFileName;
}
public void setAttachFileName(String attachFileName) {
this.attachFileName = attachFileName;
}
public String getInfo() {
return info;
}
public void setInfo(String info) {
this.info = info;
}
public String upload() throws IOException {
System.out.println(attach);
System.out.println(attachContentType);
System.out.println(attachFileName);
System.out.println(info);
FileUtils.copyFile(attach,new File(savePath+attachFileName));
return SUCCESS;
}
}
文件的下載
視圖類型一定是stream類型
頁面：
<%--
Created by IntelliJ IDEA.
User: bin
Date: 2020-07-02
Time: 9:21
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" isELIgnored="false" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<table border="1" width="300xp">
<tr>
<td>編號</td>
<td>文件名稱</td>
<td>操作</td>
</tr>
<c:forEach items="${requestScope.list}" var="list" varStatus="downStu">
<tr>
<td>${downStu.count}</td>
<td>${list}</td>
<td><a href="${pageContext.request.contextPath}/down?name=${list}">下載</a></td>
</tr>
</c:forEach>
</table>
</body>
</html>
struts。xml：
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.5//EN"
"http://struts.apache.org/dtds/struts-2.5.dtd">
<struts>
<package name="down" extends="struts-default" namespace="/">
<action name="downlist" class="com.bin.action.DownLoad" method="downLoad">
<param name="downPath">e:/images/</param>
<result name="list">downlist.jsp</result>
</action>
<action name="down" class="com.bin.action.DownLoad" method="down">
<param name="downPath">e:/images/</param>
<result name="down" type="stream">
<!-- 往StreamResult類中的屬性注入內容 -->
<!-- 返回給瀏覽器的文件類型。返回通用的二進制 -->
<param name="contentType">application/octet-stream</param>
<!-- 返回給瀏覽器的輸入流 -->
<param name="inputName">inputStream</param>
<!-- 告訴瀏覽器的方式下載資源
${name}: 獲取Action中的getName()方法的數據
-->
<param name="contentDisposition">attachment;filename=${name}</param>
<!-- 緩存大小 -->
<param name="bufferSize">1024</param>
</result>
</action>
</package>
</struts>
action：
package com.bin.action;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.InputStream;
public class DownLoad extends ActionSupport {
private String downPath;
private String name;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getDownPath() {
return downPath;
}
public void setDownPath(String downPath) {
this.downPath = downPath;
}
public String downLoad(){
File file =new File(downPath);
String[] list = file.list();
ActionContext requestMap = ActionContext.getContext();
requestMap.put("list",list);
return "list";
}
//給struts提供寫出數據的輸入流
public InputStream getInputStream(){
try {
FileInputStream inputStream = new FileInputStream(new File(downPath + name));
return inputStream;
} catch (FileNotFoundException e) {
e.printStackTrace();
throw new RuntimeException(e);
}
}
public String down(){
return "down";
}
}
這是我自己寫的一個小案例，如果又什麼地方看不懂的話，歡迎隨時提問，也可以加我的微信13283840906，只限小白，大神勿擾。