I'm not sure if I'm allowed to ask these types of questions here since it's not a problem per say, so please let me know. But I was wondering for the login.html template on Django:

{% extends 'learning_logs/base.html' %}

{% block content %} 

    {% if form.errors %}
        <p>Your username and password didn't match. Please try again.</p>
    {% endif %}

    <form method = "post" action="{% url 'login' %}">
        {% csrf_token %}
        {{ form.as_p }}

        <button name = "submit">log in</button>
        <input type="hidden" name="next" value="{% url 'learning_logs:index' %}" />
    </form>

{% endblock content %}

How come it checks for the form.errors before the it even processes the form? Thanks for any help on this question.

CodePudding user response：

The template ordering doesn't define how the form logic works, only how certain items are displayed. You could put the {% if form.errors %} block after the <form> and there would be no difference to how the form is processed by Django. Furthermore, form.errors will only exist once a form has been validated with is_valid() and any errors exist.