从表单中获取数据并在模板中显示

Question

我正在尝试从 django 教程中修改帖子应用程序-https://github.com/codingforentrepreneurs/Advancing-the-Blog/tree/master/src/posts

我正在 forms.py 中创建一个新字段“userc”：

   userc = forms.ModelChoiceField(queryset=User.objects.filter(is_staff=True))

我尝试了各种方法，但无法在模板中显示所选用户。

我应该在views.py中添加什么？

编辑： 我试过 {{ obj.userc }}, {{ instance.userc }} 在模板中显示选定的用户。

views.py

from django.contrib import messages
from django.contrib.contenttypes.models import ContentType
from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger

from django.db.models import Q
from django.http import HttpResponse, HttpResponseRedirect, Http404
from django.shortcuts import render, get_object_or_404, redirect
from django.utils import timezone

from comments.forms import CommentForm
from comments.models import Comment
from .forms import PostForm
from .models import Post

from django.contrib.auth.models import User

def post_create(request):
    if not request.user.is_staff or not request.user.is_superuser:
        raise Http404

    form = PostForm(request.POST or None, request.FILES or None)
    if form.is_valid():
        instance = form.save(commit=False)
        instance.user = request.user
        instance.save()
        # message success
        messages.success(request, "Successfully Created")
        return HttpResponseRedirect(instance.get_absolute_url())
    context = {
        "form": form,
    }
    return render(request, "post_form.html", context)





def abc(request):

    if request.method == "POST":
      #Get the posted form
      form = PostForm(request.POST)

      if form.is_valid():
         userc = form.cleaned_data['userc']
    return render(request, 'post_detail.html', {"selected_user" : userc})

















def post_detail(request, slug=None):
    instance = get_object_or_404(Post, slug=slug)
    if instance.publish > timezone.now().date() or instance.draft:
        if not request.user.is_staff or not request.user.is_superuser:
            raise Http404
    share_string = quote_plus(instance.content)




    initial_data = {
            "content_type": instance.get_content_type,
            "object_id": instance.id
    }
    form = CommentForm(request.POST or None, initial=initial_data)
    if form.is_valid() and request.user.is_authenticated():
        c_type = form.cleaned_data.get("content_type")
        content_type = ContentType.objects.get(model=c_type)
        obj_id = form.cleaned_data.get('object_id')
        content_data = form.cleaned_data.get("content")
        parent_obj = None
        try:
            parent_id = int(request.POST.get("parent_id"))
        except:
            parent_id = None

        if parent_id:
            parent_qs = Comment.objects.filter(id=parent_id)
            if parent_qs.exists() and parent_qs.count() == 1:
                parent_obj = parent_qs.first()


        new_comment, created = Comment.objects.get_or_create(
                            user = request.user,
                            content_type= content_type,
                            object_id = obj_id,
                            content = content_data,
                            parent = parent_obj,
                        )
        return HttpResponseRedirect(new_comment.content_object.get_absolute_url())


    comments = instance.comments
    context = {
        "title": instance.title,
        "instance": instance,
        "share_string": share_string,
        "comments": comments,
        "comment_form":form,
    }
    return render(request, "post_detail.html", context)

def post_list(request):
    today = timezone.now().date()
    queryset_list = Post.objects.active() #.order_by("-timestamp")
    if request.user.is_staff or request.user.is_superuser:
        queryset_list = Post.objects.all()

    query = request.GET.get("q")
    if query:
        queryset_list = queryset_list.filter(
                Q(title__icontains=query)|
                Q(content__icontains=query)|
                Q(user__first_name__icontains=query) |
                Q(user__last_name__icontains=query)
                ).distinct()
    paginator = Paginator(queryset_list, 8) # Show 25 contacts per page
    page_request_var = "page"
    page = request.GET.get(page_request_var)
    try:
        queryset = paginator.page(page)
    except PageNotAnInteger:
        # If page is not an integer, deliver first page.
        queryset = paginator.page(1)
    except EmptyPage:
        # If page is out of range (e.g. 9999), deliver last page of results.
        queryset = paginator.page(paginator.num_pages)


    context = {
        "object_list": queryset, 
        "title": "List",
        "page_request_var": page_request_var,
        "today": today,
    }
    return render(request, "post_list.html", context)





def post_update(request, slug=None):
    if not request.user.is_staff or not request.user.is_superuser:
        raise Http404
    instance = get_object_or_404(Post, slug=slug)
    form = PostForm(request.POST or None, request.FILES or None, instance=instance)
    if form.is_valid():
        instance = form.save(commit=False)
        instance.save()
        messages.success(request, "<a href='#'>Item</a> Saved", extra_tags='html_safe')
        return HttpResponseRedirect(instance.get_absolute_url())

    context = {
        "title": instance.title,
        "instance": instance,
        "form":form,
    }
    return render(request, "post_form.html", context)



def post_delete(request, slug=None):
    if not request.user.is_staff or not request.user.is_superuser:
        raise Http404
    instance = get_object_or_404(Post, slug=slug)
    instance.delete()
    messages.success(request, "Successfully deleted")
    return redirect("posts:list")

Answer 1

到目前为止，您在 forms.py 和 views.py 中的代码很好。但是，要在post_detail.html 和post_list.html 模板中显示userc，您需要在提交表单时将该字段保存到数据库中。

一种方法是在Post 模型中添加一个userc 字段：

1. 将userc = models.ForeignKey(settings.AUTH_USER_MODEL, related_name='userc', default=1) 添加到posts/models.py 中的Post 类
2. 在命令行上运行python manage.py makemigrations posts，然后运行python manage.py migrate（确保您首先位于src 目录中）

现在，在post_detail.html 模板中，您可以添加{{ instance.userc }} 以显示所选用户。

注意：related_name='userc' 是必需的，因为Post 已经有用户模型的外键。

Answer 2

将实例作为上下文变量传递。

context = { "form": form, "instance": instance }

如果 request.method 不是 POST，则在之前设置 instance = None 以使其工作。模板只能访问在视图中作为上下文传递的变量。所以在上下文中传递实例会让你使用{{instance.userc}}。

CodingforEntrepenuers 是一个出色的教程，但我建议您更密切地学习并正确掌握基础知识。