错误:"TypeError:hidden_​​tag()缺少1个必需的位置参数:'self'"在Flask，Python中 [英] Error: "TypeError: hidden_tag() missing 1 required positional argument: 'self' " in Flask, python

问题描述

我一直在创建一个基于论坛的学习系统，类似于评估项目的堆栈溢出.我对flask非常陌生，但是我相信我对python有一个不错的了解.我一直在关注 Corey Schafer's Flask教程并将其适应我的项目.每当我尝试访问名为"adduser"的页面(带有添加用户表单的网页)时，都会收到错误消息:

I've been creating a forum based learning system, similar to stack overflow for an assessed project. I'm fairly new to flask, however I believe i have a decent understanding of python. I have been following Corey Schafer's Flask tutorials and adapting them to my project. Whenever I try to access the page called 'adduser', a webpage with a form for adding users, I get the error:

"TypeError: hidden_tag() missing 1 required positional argument: 'self'".

我不知道这意味着什么，甚至不知道如何解决它. 我以为我可以在HTML中找到"adduser"页面的修复程序，并且在删除'{{ form.hidden_tag() }}'标记后，我遇到了另一个错误，这使我相信该错误与文件和'addUser.html'文件.

I have no idea what this means or how to even attempt to fix it. I assumed that I might find the fix in the HTML for the 'adduser' page, and after removing the '{{ form.hidden_tag() }}' tag, I got a different error, which leads me to believe that the error is has something to do with the 'forms.py' file and the 'addUser.html' file.

forms.py

forms.py

from flask_wtf import FlaskForm
from wtforms import StringField, PasswordField, SubmitField, BooleanField
from wtforms.validators import DataRequired, Length, Email, EqualTo, ValidationError
from itroom.models import User

class LoginForm(FlaskForm):
    email = StringField('Email',validators=[DataRequired(), Email()])
    password = PasswordField('Password', validators=[DataRequired()])
    remember = BooleanField('Remember Me')
    submit = SubmitField('Login')

class AddUserForm(FlaskForm):
    email = StringField('Email',validators=[DataRequired(), Email()])
    password = PasswordField('Password', validators=[DataRequired()])
    submit = SubmitField('Add User')

    def validate_email(self,email):
        user = User.query.filter_by(userEmail=email.data).first()
        if user:
            raise ValidationError('Email already exists in database.')

addUser.html

addUser.html

{% extends "template.html" %}
{% block content %}

  <div class="center2" style="border-color: white;">
  <h2 align="center" style="padding: 2.5%;"></h2>
    <h1>Add a User</h1>   
      <form method="POST" action="">
         {{ form.hidden_tag() }}
        <div class="form-group">
          {{form.email.label}}
          {% if form.email.errors %}
          {{form.email(size=30, class="form-control is-invalid")}}
        <div class="invalid-feedback">
          {% for error in form.email.errors %}
          <span>{{ error }}</span>
          {% endfor %}
        </div>
          {% else %}
          {{form.email(size=30, class="form-control")}}
          {% endif %}
        </div>
          {{form.password.label}} <br>
          {{form.password(size=30)}}

          {{form.submit(class="btn btn-outline-info")}} <br>

      </form>
      </div>
{% endblock content %}

我还认为路线文件也可能会有所帮助.

I also thought the routes file may be helpful aswell.

routes.py

routes.py

from flask import Flask, render_template, url_for, flash, redirect
from itroom import app, db, bcrypt
from itroom.forms import LoginForm, AddUserForm
from itroom.models import User, Post
from flask_login import login_user

@app.route("/")
@app.route("/home")     #defines the HTML loaded for /home
def home():
    return render_template('home.html', title='Home')


@app.route("/login", methods=['GET', 'POST'])       #defines the HTML loaded for /login
def login():
    form = LoginForm('')
    if form.validate_on_submit():
        user = User.query.filter_by(email=form.userEmail.data).first()
        if user and bcrypt.check_password_hash(user.userPassword, form.password):
            login_user(user, remember=form.remember.data)
            return redirect(url_for('home'))
        else:
            flash('Login Unsucessful, Please check email and password') 
    return render_template('login.html',form=form, title='Login')

@app.route("/adduser", methods=['GET', 'POST'])       #defines the HTML loaded for /adduser
def addUser():
    form = AddUserForm('/login')
    if form.validate_on_submit():
        hashed_password = bcrypt.generate_password_hash(form.password.data).decode ('utf-8')
        user = User(userEmail=form.email.data, userPassword = hashed_password)
        db.session.add(user)
        db.session.commit()
        temptext = ("Account created for '", form.email.data, "'." )
        flash(temptext)

    else:
        flash('Account not created')
    return render_template('addUser.html', title='Admin', form=AddUserForm)

在此先感谢您尝试帮助您的人！

Thank you in advance for anyone who tries to help!

推荐答案

TypeError表示自身未传递给hidden_​​tag方法.如果您不小心执行以下操作，则可能会出现此错误:

The TypeError is saying that self was not passed to the hidden_tag method. You can have this error if you do the following by accident:

class A:
    def test(self):
        print('test')

A.test() # TypeError: test() missing 1 required positional argument: 'self'
A().test() # prints test

因此，这意味着您正在使用类对象来调用该方法.

So this means that you are calling the method with a class object.

在您的路线中，您具有将某类传递到页面的以下规则，但您可能希望返回实际的表单对象.所以你必须改变

In your routes, you have the following rule where you pass a class to your page, but you likely wanted to return your actual form object. So you have to change

return render_template('addUser.html', title='Admin', form=AddUserForm)

到

form = AddUserForm('/login')
...
return render_template('addUser.html', title='Admin', form=form)

这篇关于错误:"TypeError:hidden_​​tag()缺少1个必需的位置参数:'self'"在Flask，Python中的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！