Question

springmvc作为后台该如何接收并返回数据

Answer 1

1、直接把表单的参数写在Controller相应的方法的形参中
案例：
/**
* 1.直接把表单的参数写在Controller相应的方法的形参中
*/
@RequestMapping("/add")
public String add(String username,String password) {
System.out.println("username is:"+username);
System.out.println("password is:"+password);
return "index";
}
2、通过HttpServletRequest接收
案例：
/**
* 2、通过HttpServletRequest接收
*/
@RequestMapping("/add")
public String add(HttpServletRequest request) {
String username=request.getParameter("username");
String password=request.getParameter("password");
System.out.println("username is:"+username);
System.out.println("password is:"+password);
return "index";
}
3、通过一个bean来接收
案例：

public class User {

private Long id;
private String username;
private String password;

public User(){}

public Long getId() {
return id;
}

public String getUsername() {
return username;
}

public String getPassword() {
return password;
}

public void setId(Long id) {
this.id = id;
}

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

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

}
/**
* 3、通过一个bean来接收
*/
@RequestMapping("/add")
public String add(User user) {
System.out.println("username is:"+user.getUsername());
System.out.println("password is:"+user.getPassword());
return "index";
}
4、通过@PathVariable获取路径中的参数
案例：
/**
* 4、通过@PathVariable获取路径中的参数
* @param username
* @param password
* @return
*/
@RequestMapping(value="/add/{username}/{password}",method=RequestMethod.GET)
public String addUser4(@PathVariable String username,@PathVariable String password) {
System.out.println("username is:"+username);
System.out.println("password is:"+password);
return "index";
}
访问路径 http://localhost/Demo/demo/add/cy/111111