layout: post
title: Struts2获取域和表单参数
subtitle: Struts2获取域和表单参数
date: 2018-05-31
author: ZL
header-img: img/20180531.jpg
catalog: true
tags:
- Struts
访问Servlet API
ActionContext
每次请求时都会创建一个对应的ActionContext对象，请求处理完ActionContext销毁。
如何获取ActionContext
struts2的设计是，将ActionContext对象创建好之后，将ActionContext与当前线程绑定，需要获取ActionContext对象，只需要从ThreadLocal中获取即可。
public String execute() throws Exception {
//request域=> map (struts2并不推荐使用原生request域)
//不推荐
Map<String, Object> requestScope = (Map<String, Object>) ActionContext.getContext().get("request");
//推荐,把这个当request域来用。
ActionContext.getContext().put("name", "requestTom");
//session域 => map
Map<String, Object> sessionScope = ActionContext.getContext().getSession();
sessionScope.put("name", "sessionTom");
//application域=>map
Map<String, Object> applicationScope = ActionContext.getContext().getApplication();
applicationScope.put("name", "applicationTom");
return SUCCESS;
}
ServletActionContext(不推荐)
public String execute() throws Exception {
//原生request
HttpServletRequest request = ServletActionContext.getRequest();
//原生session
HttpSession session = request.getSession();
//原生response
HttpServletResponse response = ServletActionContext.getResponse();
//原生servletContext
ServletContext servletContext = ServletActionContext.getServletContext();
return SUCCESS;
}
实现接口
//如何在action中获得原生ServletAPI
public class Demo7Action extends ActionSupport implements ServletRequestAware {
private HttpServletRequest request;
public String execute() throws Exception {
System.out.println("原生request:"+request);
return SUCCESS;
}
@Override
public void setServletRequest(HttpServletRequest request) {
this.request = request;
}
获取参数
注意Action中属性的名字应和form表中的数据一致。
属性驱动获得参数
直接在Action内部建立和参数名称相同的属性，然后设置set、get方法，就可以自动将表单数据获取到Action中的属性中了。
<form action="${pageContext.request.contextPath}/Demo8Action">
用户名:<input type="text" name="name" /><br>
年龄:<input type="text" name="age" /><br>
生日:<input type="text" name="birthday" /><br>
<input type="submit" value="提交" />
</form>
package cn.itheima.c_param;
import java.util.Date;
import com.opensymphony.xwork2.ActionSupport;
//struts2如何获得参数
//每次请求Action时都会创建新的Action实例对象
public class Demo8Action extends ActionSupport {
public Demo8Action() {
super();
System.out.println("demo8Action被创建了!");
}
//准备与参数键名称相同的属性
private String name;
//自动类型转换 只能转换8大基本数据类型以及对应包装类
private Integer age;
//支持特定类型字符串转换为Date ,例如 yyyy-MM-dd
private Date birthday;
public String execute() throws Exception {
System.out.println("name参数值:"+name+",age参数值:"+age+",生日:"+birthday);
return SUCCESS;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
}
对象驱动获得参数
bean类
<form action="${pageContext.request.contextPath}/Demo9Action">
用户名:<input type="text" name="user.name" /><br>
年龄:<input type="text" name="user.age" /><br>
生日:<input type="text" name="user.birthday" /><br>
<input type="submit" value="提交" />
</form>
//struts2如何获得参数-方式2
public class Demo9Action extends ActionSupport {
//准备user对象
private User user;
public String execute() throws Exception {
System.out.println(user);
return SUCCESS;
}
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
}
}
package cn.itheima.domain;
import java.util.Date;
public class User {
private String name;
private Integer age;
private Date birthday;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
@Override
public String toString() {
return "User [name=" + name + ", age=" + age + ", birthday=" + birthday + "]";
}
}
模型驱动获取参数
<form action="${pageContext.request.contextPath}/Demo10Action">
用户名:<input type="text" name="name" /><br>
年龄:<input type="text" name="age" /><br>
生日:<input type="text" name="birthday" /><br>
<input type="submit" value="提交" />
</form>
public class Demo10Action extends ActionSupport implements ModelDriven<User> {
//准备user 成员变量
private User user =new User();
public String execute() throws Exception {
System.out.println(user);
return SUCCESS;
}
@Override
public User getModel() {
return user;
}
}
package cn.itheima.domain;
import java.util.Date;
public class User {
private String name;
private Integer age;
private Date birthday;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
@Override
public String toString() {
return "User [name=" + name + ", age=" + age + ", birthday=" + birthday + "]";
}
}
集合类型封装
获取表单数据到list、map中。
<form action="${pageContext.request.contextPath}/Demo11Action" method="post" >
添加一个数据到list
list:<input type="text" name="list" /><br>
添加一个数据到list的第四个位置
list:<input type="text" name="list[3]" /><br>
添加一个数据到map，键是“haha”
map:<input type="text" name="map['haha']" /><br>
<input type="submit" value="提交" />
</form>
package cn.itheima.c_param;
import java.util.List;
import java.util.Map;
import com.opensymphony.xwork2.ActionSupport;
//struts2 封装集合类型参数
public class Demo11Action extends ActionSupport {
//list
private List<String> list;
//Map
private Map<String,String> map;
public String execute() throws Exception {
System.out.println("list:"+list);
System.out.println("map:"+map);
return SUCCESS;
}
public List<String> getList() {
return list;
}
public void setList(List<String> list) {
this.list = list;
}
public Map<String, String> getMap() {
return map;
}
public void setMap(Map<String, String> map) {
this.map = map;
}
}
