Question

struts2，如何在action中获取前台页面元素？

有个上传页面，form已正确设置enctype，然后添加<s:file name="file" id="file"/><s:submit/>，如何在后台获取选择文件后显示在文本框的那个路径？比如页面上我选择文件E:\test.txt，如何在后台bean中获取该路径，并用在action中？请认真回答，谢绝转载
先谢谢下面的回答，不过我最关心的是前台数据如何传递到后台，action中直接写get方法可以，是不是还有其他方法呢？比如通过bean获取，该怎么获取？谢谢

Answer 1

struts2的文件上传已经进一步简化了。

给你看个Demo

package com.test.action;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.List;

import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionSupport;

/**
* struts2文件上传
*
* @author Peerless
*
*/
@SuppressWarnings("serial")
public class UploadAction extends ActionSupport {

private String username;

private String password;

private List<File> file; // 用数组或集合处理多文件，单文件去掉集合即可。

private List<String> fileFileName;

private List<String> fileContentType;

public String getUsername() {
return username;
}

public void setUsername(String username) {
this.username = username;
}

public String getPassword() {
return password;
}

public void setPassword(String password) {
this.password = password;
}

public List<File> getFile() {
return file;
}

public void setFile(List<File> file) {
this.file = file;
}

public List<String> getFileFileName() {
return fileFileName;
}

public void setFileFileName(List<String> fileFileName) {
this.fileFileName = fileFileName;
}

public List<String> getFileContentType() {
return fileContentType;
}

public void setFileContentType(List<String> fileContentType) {
this.fileContentType = fileContentType;
}

@Override
public String execute() throws Exception {
for (int i = 0; i < file.size(); ++i) {
InputStream is = new FileInputStream(file.get(i));

String root = ServletActionContext.getRequest().getRealPath("/upload");

File destFile = new File(root, this.getFileFileName().get(i));

OutputStream os = new FileOutputStream(destFile);

byte[] buffer = new byte[400];

int length = 0;

while ((length = is.read(buffer)) > 0) {
os.write(buffer, 0, length);
}

is.close();

os.close();
}

return SUCCESS;

}

}

Answer 2

前台jsp页面获取后台值的方式
<s:property value="#request.requestKey"/>|<%=request.getAttribute("requestKey")%>
<s:property value="#session.sessionKey"/>|<%=session.getAttribute("sessionKey")%>
<s:property value="#application.applicationKey"/>|<%=application.getAttribute("applicationKey")%>