如何使用 django 中的 ManyToMany 访问另一个 model 或表的属性

Question

Please, I need your help. How can I access to attribut of another model or table using ManyToMany

I need to get data through this method but it's not retrieved

---=> this is Models.py

class Mission(models.Model):
        nom=models.CharField(max_length=50,null=False,blank=False)
        description=models.CharField(max_length=150,null=False,blank=False)  
        date_publier=models.DateTimeField()  

class Participer(models.Model):
    id_benevole =  models.ManyToManyField(User)
    id_mission =  models.ManyToManyField(Mission)
    est_participer = models.BooleanField(default=False)

class  User(AbstractUser):
    est_association = models.BooleanField(default=False)
    est_benevolat = models.BooleanField(default=False)
    username = models.CharField(max_length=30,unique=True)
    email = models.EmailField()
    password1 = models.CharField(max_length=20,null=True)
    password2 = models.CharField(max_length=20,null=True)

class ProfileBenevole(models.Model):
   user = models.OneToOneField(User,related_name="benevole", on_delete = models.CASCADE, 
    primary_key = True)
    photo_profile = models.ImageField( upload_to='uploads/images',null=True,blank=True)
    nomComplet = models.CharField(max_length=50,null=True)

--=> this is Views.py

def demande_participer(request):
  participers=Participer.objects.all()
return render(request,'Association/success.html', {'participers':participers},print(participers))

----=> success.html

{% extends 'home/base.html'%}
{% block content %}{% load static %}
<div class=" mt-4 pb-5">
    <h1 style="text-align:center;">Confirmation de Participation </h1>
    <div class="container">
    <div class="card mt-5 pb-5">
       {% for parti in participers %}
      
       {{parti.mission_id.nom}}
       <br>
       {{parti.id_benevole.username}}
       <br>
       {{parti.est_participer}}
       {% endfor%}
       
     </div>
    
    <a class="btn btn-secondary mt-2 " href="{% url 'benevole' %}">Retour </a>
    </div>
</div>
{% endblock content %}

Answer 1

Since you have a ManyToMany relationship, every Participer can have multiple Missions and Users. It therefor makes no sense to get an attribute of one of the (potentially) multiple related objects.

Either change the ManyToMany to a ForeignKey in your Participer model, or loop through all related objects in your template. Something like (I did not test this code):

{% for parti in participers %}
    {% for benevole in parti.id_benevole.all %}
        {{ benevole.username }}
    {% endfor %}
{% endfor %}

Judging by the names you give your model fields, I think switching from ManyToMany to ForeignKey is your best option here.