How do I display the value of a Django form field in a template?

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I have a form with an email property.

When using {{ form.email }} in case of some validation error, Django still renders the previous value in the input tag's value attribute:

<input type="text" id="id_email" maxlength="75" class="required"
       value="some@email.com" name="email">

I want to render the input tag myself (to add some JavaScript code and an error class in case of an error). For example this is my template instead of {{ form.email }}:

<input type="text" autocomplete="on" id="id_email" name="email"
       class="email {% if form.email.errors %} error {% endif %}">

However, this does not display the erroneous value (some@email.com in this example) to the user.

How do I get the field's value in the template?

12 Answers

You can do this from the template with something like this:

{% if form.instance.some_field %}
      {{form.instance.some_field}}
{% else %}
      {{form.data.some_field}}
{% endif %}

This will display the instance value (if the form is created with an instance, you can use initial instead if you like), or else display the POST data such as when a validation error occurs.

I have a simple solution for you!

{{ form.data.email }}

I tried this and it worked. This requires your view to populate the form class with the POST data.

Very simple example:

def your_view(request):
  if request.method == 'POST':
    form = YourForm(request.POST)
    if form.is_valid():
      # some code here
  else:
    form = YourForm()

  return render_to_response('template.html', {'form':form})

Hope that helps you. If you have any questions please let me know.

The solution proposed by Jens is correct. However, it turns out that if you initialize your ModelForm with an instance (example below) django will not populate the data:

def your_view(request):   
    if request.method == 'POST':
        form = UserDetailsForm(request.POST)
        if form.is_valid():
          # some code here   
        else:
          form = UserDetailsForm(instance=request.user)

So, I made my own ModelForm base class that populates the initial data:

from django import forms 
class BaseModelForm(forms.ModelForm):
    """
    Subclass of `forms.ModelForm` that makes sure the initial values
    are present in the form data, so you don't have to send all old values
    for the form to actually validate.
    """
    def merge_from_initial(self):
        filt = lambda v: v not in self.data.keys()
        for field in filter(filt, getattr(self.Meta, 'fields', ())):
            self.data[field] = self.initial.get(field, None)

Then, the simple view example looks like this:

def your_view(request):   if request.method == 'POST':
    form = UserDetailsForm(request.POST)
    if form.is_valid():
      # some code here   
    else:
      form = UserDetailsForm(instance=request.user)
      form.merge_from_initial()

For check box with its items:

{% for item in people.q %}
    <div class="form-check form-switch ">
    <label class="form-check-label" for="{{ item.id_for_label }}">{{ item.data.label }}</label>
    <input class="form-check-input" type="checkbox" id="{{ item.id_for_label }}" value="{{ item.data.value }}">
     </div>
{% endfor %}

q is field name.

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