flash send error python code example
Example 1: flask flash
{% with messages = get_flashed_messages(with_categories=true) %}
{% if messages %}
{% for category, message in messages %}
<div class="alert alert-{{ category }} alert-dismissible fade show" role="alert">
<span>{{ message }}</span>
<button type="button" class="close" data-dismiss="alert" aria-label="Close">
<span aria-hidden="true">×</span>
</button>
</div>
{% endfor %}
{% endif %}
{% endwith %}
Example 2: custom flask messages python
from flask import Flask, flash, redirect, render_template, \
request, url_for
app = Flask(__name__)
app.secret_key = b'_5#y2L"F4Q8z\n\xec]/'
@app.route('/')
def index():
return render_template('index.html')
@app.route('/login', methods=['GET', 'POST'])
def login():
error = None
if request.method == 'POST':
if request.form['username'] != 'admin' or \
request.form['password'] != 'secret':
error = 'Invalid credentials'
else:
flash('You were successfully logged in')
return redirect(url_for('index'))
return render_template('login.html', error=error)