当用户尝试使用已被占用的电子邮件或用户名进行注册时,我试图向他们显示验证错误。
但是,尽管它确实有效,但当我运行 Web 开发服务器时,我在网页上看不到任何内容。
这里是验证错误的Python代码:
from flask_wtf import FlaskForm
from wtforms import StringField, PasswordField, SubmitField, BooleanField
from wtforms.validators import DataRequired, Length, Email, EqualTo, ValidationError
from flaskblog.models import User
class RegistrationForm(FlaskForm):
username = StringField('Username',
validators=[DataRequired(), Length(min=2, max=20)])
email = StringField('Email',
validators=[DataRequired(), Email()])
password = PasswordField('Password', validators=[DataRequired()])
confirm_password = PasswordField('Confirm Password',
validators=[DataRequired(), EqualTo('password')])
submit = SubmitField('Sign Up')
def validate_username(self, username):
user = User.query.filter_by(username=username.data).first()
if user:
raise ValidationError('That username is taken. Please choose a different one.')
def validate_email(self, email):
email = User.query.filter_by(email=email.data).first()
if email:
raise ValidationError('That email is taken. Please choose a different one.')
class LoginForm(FlaskForm):
email = StringField('Email',
validators=[DataRequired(), Email()])
password = PasswordField('Password', validators=[DataRequired()])
remember = BooleanField('Remember Me')
submit = SubmitField('Login')
但是即使轮廓是红色的,我也看不到消息:
我不确定它是否有用,但这也是我用于页面通用渲染的layout.html代码:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
<link rel="stylesheet" type="text/css" href="{{ url_for('static', filename='main.css') }}">
{% if title %}
<title>Flask Blog - {{ title }} </title>
{% else %}
<title>Flask Blog</title>
{% endif %}
</head>
<body>
<header class="site-header">
<nav class="navbar navbar-expand-md navbar-dark bg-steel fixed-top">
<div class="container">
<a class="navbar-brand mr-4" href="/">Flask Blog</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarToggle" aria-controls="navbarToggle" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarToggle">
<div class="navbar-nav mr-auto">
<a class="nav-item nav-link" href="{{ url_for('home') }}">Home</a>
<a class="nav-item nav-link" href="{{ url_for('about') }}">About</a>
</div>
<!-- Navbar Right Side -->
<div class="navbar-nav">
<a class="nav-item nav-link" href="{{ url_for('login') }}">Login</a>
<a class="nav-item nav-link" href="{{ url_for('register') }}">Register</a>
</div>
</div>
</div>
</nav>
</header>
<main role="main" class="container">
<div class="row">
<div class="col-md-8">
{% with messages = get_flashed_messages(with_categories=true) %}
{% if messages %}
{% for category, message in messages %}
<div class="alert alert-{{ category }}">
{{ message }}
</div>
{% endfor %}
{% endif %}
{% endwith %}
{% block content %}{% endblock %}
</div>
<div class="col-md-4">
<div class="content-section">
<h3>Our Sidebar</h3>
<p class='text-muted'>You can put any information here you'd like.
<ul class="list-group">
<li class="list-group-item list-group-item-light">Latest Posts</li>
<li class="list-group-item list-group-item-light">Announcements</li>
<li class="list-group-item list-group-item-light">Calendars</li>
</ul>
</p>
</div>
</div>
</div>
</main>
<!-- Optional JavaScript -->
<!-- jQuery first, then Popper.js, then Bootstrap JS -->
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js" integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl" crossorigin="anonymous"></script>
</body>
</html>
这里一切看起来都不错,但是当您渲染此模板时,您可能会缺少参数。确保所有内容都正确导入那里。 & 您是否可以分享渲染模板的渲染模板代码?