struts2总结四:Action与Form表单的交互

struts2 Action获取表单数据的方式有三种:1.通过属性驱动的方式。2.模型驱动方式。3.使用多个model对象的属性。

1.通过属性驱动式

首先在jsp里面编写form表单的代码如下:

    <form action="sys/login.action" method="post">  
        <input type="text" name="username">  
        <input type="submit" value="submit">  
    </form>

Action:直接通过get、set方法获取。代码如下:

public class sysAction extends ActionSupport{  
    private String username;  
 
    public String login() throws Exception {  
        System.out.println(username);  
        return SUCCESS;  
    }  
 
    public String getUsername() {  
        return username;  
    }  
    public void setUsername(String username) {  
        this.username= username;  
    }  
}   

2.模型驱动方式，Action类必须要实现ModelDriven<T>接口。对于要传入多个model第二种方式不方便

首先在jsp里面编写form表单的代码如下:

    <form action="sys/login.action" method="post">  
        <input type="text" name="username">  
        <input type="submit" value="submit">  
    </form>

 Action:必须实现getModel() 方法,代码如下所示:

public class sysAction extends ActionSupport implements ModelDriven<User>{  
    private User user;  
 
    public String login() throws Exception {  
        System.out.println(getModel().getUsername());  
        return SUCCESS;  
    }  
 
    public User getModel() {  
        if (null == user) {  
            return user = new User();  
        }  
        return user;  
    }  
}   

3.第三种方式可以完全不实现ModelDriven<T>，也可使用多个model对象的属性。

首先在jsp里面编写form表单的代码如下:

 <form action="sys/login.action" method="post">  
        <input type="text" name="username">  
        <input type="submit" value="submit">  
    </form>

Action: 必须提供set方法

public class sysAction extends ActionSupport{  
    private User user;  
    private Teacher teacher;  
 
    public String login() throws Exception {  
        System.out.println(user.getUsername());  
        System.out.println(teacher.getLevel());  
        return SUCCESS;  
    }  
 
    public void setUser(User user) {  
        this.user = user;  
    }  
    public void setTeacher(Teacher teacher) {  
        this.teacher = teacher;  
    }  
}