Struts2上傳多個檔案例子

在上章節Struts2 檔案上傳範例, 使用者允許選擇一個檔案並上傳到伺服器。在本教學中，您將學習如何允許使用者將多個檔案上傳到伺服器。

這裡建立一個Web工程：strut2uploadfiles，來演示在多個核取方塊如何設定的預設值，整個專案的結構如下圖所示：

1. 動作類

在Action類，可以使用列表或陣列以儲存上傳的檔案。

FileUploadAction.java

package com.tw511.common.action;

import java.io.File;
import java.util.ArrayList;
import java.util.List;

import com.opensymphony.xwork2.ActionSupport;

public class MultipleFileUploadAction extends ActionSupport{

	private List<File> fileUpload = new ArrayList<File>();
	private List<String> fileUploadContentType = new ArrayList<String>();
	private List<String> fileUploadFileName = new ArrayList<String>();

	public List<File> getFileUpload() {
		return fileUpload;
	}

	public void setFileUpload(List<File> fileUpload) {
		this.fileUpload = fileUpload;
	}

	public List<String> getFileUploadContentType() {
		return fileUploadContentType;
	}

	public void setFileUploadContentType(List<String> fileUploadContentType) {
		this.fileUploadContentType = fileUploadContentType;
	}

	public List<String> getFileUploadFileName() {
		return fileUploadFileName;
	}

	public void setFileUploadFileName(List<String> fileUploadFileName) {
		this.fileUploadFileName = fileUploadFileName;
	}
	
	public String upload() throws Exception{
		
	    for (File file: fileUpload) {
	        System.out.println("File :" + file);
	    }
	    
	    for (String fileName: fileUploadFileName) {
	        System.out.println("Filename : " + fileName);
	    }

	    for (String fileContentType: fileUploadContentType) {
	        System.out.println("File type : " + fileContentType);
	    }
	    
	    return SUCCESS;
		
	}

	public String display() {
		return NONE;
	}
	
}

2. 結果頁面

使用<s:file>標籤來渲染多檔案上傳元件，並設定表單 enctype型別為「multipart/form-data」.

fileupload.jsp

<%@ taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<s:head />
</head>

<body>
<h1>Struts2上傳多個檔案範例</h1>

<s:form action="resultAction" namespace="/" 
method="POST" enctype="multipart/form-data">

<s:file label="File 1" name="fileUpload" size="40" />
<s:file label="File 2" name="fileUpload" size="40" />
<s:file label="FIle 2" name="fileUpload" size="40" />

<s:submit value="submit" name="submit" />
	
</s:form>

</body>
</html>

result.jsp

<%@ taglib prefix="s" uri="/struts-tags" %>
<html>

<body>
<h1>Struts2上傳多個檔案範例</h1>

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     data-ad-client="ca-pub-2836379775501347"
     data-ad-slot="3642936086"
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<script>
(adsbygoogle = window.adsbygoogle || []).push({});
</script>
</div></div><h2>
   File Name : <s:property value="fileUploadFileName"/> 
</h2> 

<h2>
   Content Type : <s:property value="fileUploadContentType"/> 
</h2> 

<h2>
   File : <s:property value="fileUpload"/> 
</h2> 

</body>
</html>

3. struts.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">
 
<struts>

 	<constant name="struts.devMode" value="true" />

	<package name="default" namespace="/" extends="struts-default">
		
	<action name="multipleFileUploadAction" 
	    class="com.tw511.common.action.MultipleFileUploadAction" 
            method="display">
		<result name="none">pages/multiplefileupload.jsp</result>
	</action>
		
	<action name="resultAction" 
	     class="com.tw511.common.action.MultipleFileUploadAction" 
             method="upload">
		 <result name="success">pages/result.jsp</result>
	</action>
   </package>
	
</struts>

4. 範例

http://localhost:8080/struts2uploafiles/multipleFileUploadAction.action

參考

下載程式碼 -