How to display a ForeignKey field as a selection field in django template

Question

I need to display a foreignKey field as a selection field in Django template, which will show all the available records as a dropdown. On considering the case of querying to database every time on selecting the field, which is the best method to achieve above goal to make a selection field from ForeignKey field.

Answer 1

Use ModelChoiceField https://docs.djangoproject.com/en/1.10/ref/forms/fields/#django.forms.ModelChoiceField

class MyForm(forms.ModelForm):
    myfield = forms.ModelChoiceField(queryset=...)

Answer 2

You should use first views to get that foreign key field and pass it over the context dict. to the template.

Inside Views.py

DEPENDENT_FILED = DB.OBJECT.ALL() // field which has all the drop-down values.
FR_FIELD = DB.OBJECT.GET(DB_OBJ_HAVING_FR) // selected drop-down from template

context['FR_FIELD'] = FR_FIELD

Inside example.html

{% if FR_FIELD %}
    <select name="dropdown_field">
          {%for fr_key in DEPENDENT_FILED %}
               <option value="{{fr_key.field_name}}" {% if fr_key.field_name = FR_FIELD|add:0 %}selected{% endif %}>{{fr_key.option_name}}</option>
         {% endfor %}
    </select>