ModelForm的使用

from django.conf.urls import url
from django.contrib import admin
from app01 import views

urlpatterns = [
    url(r‘^admin/‘, admin.site.urls),
    url(r‘^book_list‘, views.book_list),
    url(r‘^add_book‘, views.add_book),
    url(r‘^edit_book/(\d+)‘, views.edit_book)
]

from django import forms
from app01 import models


class BookForm(forms.Form):
    title = forms.CharField(max_length=32, label="书名")
    price = forms.DecimalField(max_digits=5, decimal_places=2)
    publish_date = forms.DateField(
        widget=forms.widgets.TextInput(
            attrs={"type": "date"}
        )
    )
    # 这样写可以实现添加书籍，不能实现编辑书籍，因为编辑书籍需要显示要编辑的这本数的原来的出版社和作者
    # 即需要默认值，无法操作
    # publisher = forms.ChoiceField(
    #     choices=models.Publish.objects.all().values_list("id", "name"),
    #     widget=forms.widgets.Select()
    # )
    # authors = forms.ChoiceField(
    #     choices=models.Author.objects.all().values_list("id", "name"),
    #     widget=forms.widgets.SelectMultiple()
    # )

    # 解决上述不能实现编辑书籍的问题
    publisher = forms.ModelChoiceField(
        queryset=models.Publish.objects.all()
    )
    authors = forms.ModelMultipleChoiceField(
        queryset=models.Author.objects.all()
    )

from django.shortcuts import render, redirect
from app01 import models
from app01.myforms import BookForm
from django.forms.models import model_to_dict
# Create your views here.

# 日志操作
import logging
logger = logging.getLogger(__name__)  # 生成一个以当前文件名为名字的日志实例对象
collect_logger = logging.getLogger("collect")  # 生成一个名字是collect的日志实例对象


def book_list(request):
    book_list_obj = models.Book.objects.all()
    return render(request, "book_list.html", {"book_list_obj": book_list_obj})


# 使用一般的form组件
def add_book(request):
    form_obj = BookForm()
    # publisher = models.Publish.objects.all()  # 使用form组件不需要传了
    # authors = models.Author.objects.all()  # # 使用form组件不需要传了
    if request.method == "POST":
        form_obj = BookForm(request.POST)
        if form_obj.is_valid():
            authors = form_obj.cleaned_data.pop("authors")
            book_obj = models.Book.objects.create(**form_obj.cleaned_data)
            # book_obj.authors.add(*authors)  # 二者都可以
            book_obj.authors.set(authors)  # 既可以是对象列表，又可以是id列表
            return redirect("/book_list/")
    return render(request, "add_book.html", {"form_obj": form_obj})


def edit_book(request, pk):
    book_obj = models.Book.objects.filter(id=pk).first()
    dic_obj = model_to_dict(book_obj) # 把一个对象转换为字典的格式
    print(dic_obj)
    form_obj = BookForm(initial=dic_obj)  # 注意这里的initial，传入的是一个字典的形式，指定默认值（编辑书籍需要有默认值）
    if request.method == "POST":
        form_obj = BookForm(request.POST)
        if form_obj.is_valid():
            # form组件写的 只能一个一个写，不过变成从form_obj.cleaned_data中取值
            title = form_obj.cleaned_data.get("title")
            price = form_obj.cleaned_data.get("price")
            publish_date = form_obj.cleaned_data.get("publish_date")
            publisher = form_obj.cleaned_data.get("publisher")
            authors = form_obj.cleaned_data.get("authors")
            book_obj.title = title
            book_obj.price = price
            book_obj.publish_date = publish_date
            book_obj.publisher_id = publisher
            book_obj.save()
            book_obj.authors.set(authors)  # 可以是对象列表，又可以是id列表
            return redirect("/book_list/")
    return render(request, "edit_book.html", {"form_obj": form_obj})

from django import forms
from app01 import models

class BookModelForm(forms.ModelForm):

    class Meta:
        # 告诉Django这个form类和那个model类对应
        model = models.Book
        # 告诉Django这个form类里面有哪些字段
        fields = "__all__"  # 所有字段
        # fields = ["title", "price"]
        # exclude = ["authors"]  # 不要authors
        widgets = {
            "publish_date": forms.widgets.DateInput(
                attrs={"type": "date", "class": "form-control"}  # 也可以加bootstrap样式
            )
        }
        labels = {
            "title": "书名",
            "price": "价格",
            "publish_date": "出版日期"
        }
        error_messages = {
            "title": {
                "required": "书名不能为空"
            }
        }

from django.shortcuts import render, redirect
from app01 import models
# Create your views here.
from app01.myforms import BookModelForm
import logging

logger = logging.getLogger(__name__)  # 生成一个以当前文件名为名字的日志实例对象
collect_logger = logging.getLogger("collect")  # 生成一个名字是collect的日志实例对象


def book_list(request):
    book_list_obj = models.Book.objects.all()
    return render(request, "book_list.html", {"book_list_obj": book_list_obj})

# 使用modelform   解决上面编辑时代码重复写
def add_book(request):
    form_obj = BookModelForm()
    # publisher = models.Publish.objects.all()  # 使用form组件不需要传了
    # authors = models.Author.objects.all()  # # 使用form组件不需要传了
    if request.method == "POST":
        form_obj = BookModelForm(request.POST)
        if form_obj.is_valid():
            # 使用BookModelForm，下面的都不需要，只需save()
            # authors = form_obj.cleaned_data.pop("authors")
            # book_obj = models.Book.objects.create(**form_obj.cleaned_data)
            # # book_obj.authors.add(*authors)  # 二者都可以
            # book_obj.authors.set(authors)  # 既可以是对象列表，又可以是id列表
            form_obj.save()
            return redirect("/book_list/")
    return render(request, "add_book.html", {"form_obj": form_obj})


def edit_book(request, pk):
    # 日志打印练习
    logger.debug(‘又要编辑id值是{}的书籍了...‘.format(pk))
    logger.info(‘又要编辑id值是{}的书籍了...‘.format(pk))
    collect_logger.warning("id是{}的书籍又被人编辑了...".format(pk))

    book_obj = models.Book.objects.filter(id=pk).first()
    form_obj = BookModelForm(instance=book_obj)  # 不需要转化为字典了，直接传对象
    if request.method == "POST":
        form_obj = BookModelForm(request.POST, instance=book_obj)
        if form_obj.is_valid():
            form_obj.save()
            return redirect("/book_list/")
    return render(request, "edit_book.html", {"form_obj": form_obj})

model = models.Student  # 对应的Model中的类
fields = "__all__"  # 字段，如果是__all__,就是表示列出所有的字段
exclude = None  # 排除的字段
labels = None  # 提示信息
help_texts = None  # 帮助提示信息
widgets = None  # 自定义插件
error_messages = None  # 自定义错误信息