python - 如何在 python 中将用户输入从一个类传递到另一个类？

Question

我是编程新手，所以很可能我做错了，但这就是我正在尝试做的事情。

我正在尝试编写一个程序，该程序的表单在一个类中接受用户输入，然后将其传递给另一个类，但我不知道该怎么做。这是相关代码的片段(我将 * 放在用户名变量周围，这是我要传递的变量):

class MainHandler(webapp2.RequestHandler):
  #this is in a form
   def post(self):
    ***username*** = self.request.get('username')

  #if username and other info entered correctly, then it redirects user to a new page and the WelcomeHandler class, so how do I get the username into the "Welcome, " message below?:


class WelcomeHandler(webapp2.RequestHandler):
    def get(self):
        self.response.out.write("Welcome, " + ***username***)

编辑:这是我的全部代码，如果有帮助的话:

import webapp2
import re
import cgi

form="""

<form method = "post">   
Signup
<br>

<table>
    <tbody>            
      <tr><td><label>Username</label></td><td><input type="text" name = "username" 
 value="%(username)s"><div style="color: red">%(error)s</div> </td></tr>

<br>
     <tr><td> <label>Password</label></td><td><input type="password" name = "password" 
value="%(password)s"><div>TK TK TK</div></td></tr>

<br>
    <tr><td> <label> Verify password</label></td><td><input type="password" name = 
"verify" value="%(verify)s"><div> TK TK TK</div></td></tr>

<br>
    <tr><td> <label> Email(optional)</label></td><td><input type = "text" name = "email"
 value ="%(email)s"><div> TK TK TK</div></td></tr>

 </tbody>
</table>
<br>
<br>
<input type = "submit">
</form>
"""


def escape_html(s):
    return cgi.escape(s, quote = True)

def valid_username(username):
    USER_RE = re.compile(r"^[a-zA-Z0-9_-]{3,20}$")
    return USER_RE.match(username)

def valid_password(password):
    USER_RE = re.compile(r"^.{3,20}$")
    return USER_RE.match(password)

def verify_password(password, verify):
    if verify == password:
        return True
    else:
        return False

def valid_email(email):
    USER_RE = re.compile(r"^[\S]+@[\S]+\.[\S]+$")
    return USER_RE.match(email)

class MainHandler(webapp2.RequestHandler):
    def write_form(self, error="", username="", password="", verify="", email=""):
        self.response.out.write(form % {'error': error, "username": 
escape_html(username), "password": escape_html(password), "verify": escape_html(verify),
 "email": escape_html(email)})

    def get(self):
        self.write_form()


    def post(self):
        username = self.request.get('username')
        password = self.request.get('password')
        verify = self.request.get('verify')
        email = self.request.get('email')

        username_check = valid_username(username)
        password_check = valid_password(password)
        verify_check = verify_password(password, verify)
        email_check = valid_email(email)

        if not (username_check and password_check and verify_check):
            self.write_form("That's not valid, you jive turkey", username, password, 
verify, email)
        else:
            self.redirect("/welcome")

class WelcomeHandler(webapp2.RequestHandler):
    def get(self):
        self.response.out.write("Welcome, " + username)


app = webapp2.WSGIApplication([
        ('/', MainHandler),
        ('/welcome', WelcomeHandler)], debug=True)

Answer 1

你不想这样做。这不仅仅是普通的基于类的编程:这些类中的每一个都代表从浏览器向您的服务器发出的请求。在类之间传递该数据意味着什么？

您真正想要做的是告诉浏览器重定向到您的 GET 处理程序。