struts2中form表单中的input的类型type=file，提交时在ActionSupport如何得到他的file文件

你好按照我摘录的以下编写就可以了
Java代码
<%@ page language="java" contentType="text/html; charset=utf-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>













Java代码
<%@ page language="java" contentType="text/html; charset=utf-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>














请求处理LoginAction.java：

Java代码
package tutorial;

import com.opensymphony.xwork2.ActionSupport;

public class LoginAction extends ActionSupport {

private String msg="显示默认消息";
private String userName;
private String password;

public String getPassword() {
return password;
}

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

public String getUserName() {
return userName;
}

public void setUserName(String userName) {
this.userName = userName;
}

public String getMsg() {
return msg;
}

public String execute(){
if ("xiaozhu".equals(userName)&&"111111".equals(password)) {
msg="welcome,"+userName;
} else {
msg="用户名或密码错误";
}
return this.SUCCESS;
}
}
Java代码
package tutorial;

import com.opensymphony.xwork2.ActionSupport;

public class LoginAction extends ActionSupport {

private String msg="显示默认消息";
private String userName;
private String password;

public String getPassword() {
return password;
}

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

public String getUserName() {
return userName;
}

public void setUserName(String userName) {
this.userName = userName;
}

public String getMsg() {
return msg;
}

public String execute(){
if ("xiaozhu".equals(userName)&&"111111".equals(password)) {
msg="welcome,"+userName;
} else {
msg="用户名或密码错误";
}
return this.SUCCESS;
}
}

响应页面HelloWorld.jsp：
Java代码
<%@ page language="java" contentType="text/html; charset=utf-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>

Java代码
<%@ page language="java" contentType="text/html; charset=utf-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>

如上所示，对于login.jsp表单中的每个值域我们都会在相应的action中声明一个对应的属性并产生相应的get和set方法，如果这个表单中的值很多(例如注册用户信息的表单)，就会导致action十分庞大和容易混乱，并且也不利于我们的软件分层，违背了OO的原则，下面看一下改进后的方案。

登陆页面login.jsp：

Java代码
<%@ page language="java" contentType="text/html; charset=utf-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>













Java代码
<%@ page language="java" contentType="text/html; charset=utf-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>














新增实体类User.java：

Java代码
package tutorial;

public class User {
private String userName;
private String password;

public String getPassword() {
return password;
}

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

public String getUserName() {
return userName;
}

public void setUserName(String userName) {
this.userName = userName;
}
}
Java代码
package tutorial;

public class User {
private String userName;
private String password;

public String getPassword() {
return password;
}

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

public String getUserName() {
return userName;
}

public void setUserName(String userName) {
this.userName = userName;
}
}

请求处理LoginAction.java：
Java代码
package tutorial;

import com.opensymphony.xwork2.ActionSupport;

public class LoginAction extends ActionSupport {

private String msg="显示默认消息";
private User user;

public User getUser() {
return user;
}

public void setUser(User user) {
this.user = user;
}

public String getMsg() {
return msg;
}

public String execute(){
if("xiaozhu".equals(user.getUserName())&&"111111".equals(user.getPassword()))
msg="welcome,"+user.getUserName();
else
msg="用户名或密码错误";
return this.SUCCESS;//
}
}
Java代码
package tutorial;

import com.opensymphony.xwork2.ActionSupport;

public class LoginAction extends ActionSupport {

private String msg="显示默认消息";
private User user;

public User getUser() {
return user;
}

public void setUser(User user) {
this.user = user;
}

public String getMsg() {
return msg;
}

public String execute(){
if("xiaozhu".equals(user.getUserName())&&"111111".equals(user.getPassword()))
msg="welcome,"+user.getUserName();
else
msg="用户名或密码错误";
return this.SUCCESS;//
}
}

响应页面HelloWorld.jsp：
Java代码
<%@ page language="java" contentType="text/html; charset=utf-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>

Java代码
<%@ page language="java" contentType="text/html; charset=utf-8"%>
<%@ taglib prefix="s" uri="/struts-tags" %>

注意:
Java代码
public User getUser() {
return user;
}
Java代码
public User getUser() {
return user;
}

Action中的这个get方法必须，否则会出现丢值的现象；set方法就更不用说了，必须的。

可以查下
struts2
自带的上传功能。