在 .validate_on_submit 之后在烧瓶上闪烁错误/成功消息答案

【问题标题】：Flash a error/success message on flask after .validate_on_submit在 .validate_on_submit 之后在烧瓶上闪烁错误/成功消息
【发布时间】：2020-04-17 20:41:35
【问题描述】：

Flask 的新手和学习做一些体面的事情的时间很短（大学）。我有一项调查，我想使用 FLASH 来显示成功和错误消息（类别），虽然我无法这样做，但我对其进行了很好的研究，并且确实了解了它的工作原理，我的代码似乎与我找到的示例相比很好，但显然不是。如果有人可以帮助我，将不胜感激。

这是 .py 文件

def index():
    form = Form()
    if form.validate_on_submit():
        flash(u'Thank you for your collaboration!', 'success')
        if not form.validate_on_submit():
            flash(u'Something went wrong!', 'error')
            return redirect(url_for('index'))
        return redirect(url_for('index'))
    #submission_successful = True #or False. you can determine this.
    return render_template('index1.html', form=form) #submission_successful=submission_successful)

.html 文件

<center>
    <form methods='POST'>
        {{ form.csrf_token }}
        {{ form.hidden_tag() }}
        <div style = font-size:18px; font-weight:bold; margin-left:200px; class="form-field"> {{ form.Email.label }} <br> {{ form.Email }}  </div> <br>
        <div style = font-size:18px; font-weight:bold; margin-left:100px; class="form-field"> {{ form.sex.label }} {{ form.sex }}   </div> <br>
        <div style = font-size:18px; font-weight:bold; margin-left:100px; class="form-field"> {{ form.age.label }}  {{ form.age }}  </div> <br>
        <div style = font-size:18px; font-weight:bold; margin-left:100px; class="form-field"> {{ form.Marital.label }}  {{ form.Marital }}  </div> <br>
        <div style = font-size:18px; font-weight:bold; margin-left:100px; class="form-field"> {{ form.county.label}}  {{ form.county }}  </div> <br>
        <div style = font-size:18px; font-weight:bold; margin-left:100px; class="form-field"> {{ form.Property.label }}  {{ form.Property }}  </div> <br>
        <div style = font-size:18px; font-weight:bold; margin-left:100px; class="form-field"> {{ form.PropertyStatus.label }}  {{ form.PropertyStatus }}  </div> <br>
        <div style = font-size:18px; font-weight:bold; margin-left:100px; class="form-field"> {{ form.Rooms.label }}  {{ form.Rooms }}  </div> <br>
        <div style = font-size:18px; font-weight:bold; margin-left:100px; class="form-field"> {{ form.People.label}} <br> {{ form.People }} </div> <br>
        <div style = font-size:17px; font-weight:bold; margin-left:100px; class="form-field"> {{ form.submit}}  </div>

        {% with messages = get_flashed_messages(with_categories=true) %}
            {% if messages %}
                {% for category, message in messages %}
                {% if category == 'success'%}
                    <div class='alert alert-success mb-3' role='alert' >
                        {{ message }}
                    </div>
                {% endif %}
                {% if category == 'error'%}
                    <div class='alert alert-danger mb-3' role='alert' >
                        {{ message }}
                    </div>
                {% endif %}

                {% endfor %}
            {% endif %}
        {% endwith %}


    </center>
    </form>

【问题讨论】：

标签： python-3.x flask web-applications visual-studio-code

【解决方案1】：

这是我通常为消息闪烁所做的。 https://hastebin.com/behopumivu.cs 对不起，格式不好，我是电话。但是如果你把它放在你的基本模板中，当你“闪烁”时，它总是会在用户当前所在页面的顶部闪烁一条消息。希望这有帮助！

【讨论】：

【解决方案2】：

这是一个使用 Flash 消息的简单模板...为您的案例定制此模板

应用程序.py

from flask import Flask, render_template, redirect, url_for,session, flash
from flask_wtf import FlaskForm
from wtforms import (StringField, SubmitField)


app = Flask(__name__)

app.config['SECRET_KEY'] = 'mysecretkey'


class InfoForm(FlaskForm):
    name = StringField('What are you?')
    submit = SubmitField('Submit')


@app.route('/', methods=['GET', 'POST'])
def index():
    # Create instance of the form.
    form = InfoForm()
    # If the form is valid on submission (we'll talk about validation next)
    if form.validate_on_submit():
        # Grab the data from the breed on the form.

        session['name'] = form.name.data
        flash(f"You just changed your name to: {session['name']}")
        return redirect(url_for("index"))

    return render_template('index.html', form=form)


if __name__ == '__main__':
    app.run(debug=True)

#index.html


<html>
<head>
  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">
  <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>

</head>

<div class="container">


  {# get_flashed_messages() is auto sent to the template with the flash() call #}
      {% for mess in get_flashed_messages()  %}
      <div class="alert alert-warning alert-dismissible fade show" role="alert">
        <button type="button" class="close" data-dismiss="alert" aria-label="Close" class="fade close">
          <span aria-hidden="true">&times;</span>
        </button>
        {{mess}}
        </div>
      {% endfor %}


<form method="POST">
    {# This hidden_tag is a CSRF security feature. #}
    {{ form.hidden_tag() }}
    {{ form.name.label }} {{ form.name() }}
    {{ form.submit() }}
</form>
</div>
</html>

【讨论】：

伙计，你是一个活生生的救星。我得到了它的设置，我会调整我的代码。谢谢。一旦它起作用，我会将答案标记为正确。