ModelForm组件怎么在Django中使用-创新互联
本篇文章为大家展示了ModelForm组件怎么在Django中使用,内容简明扼要并且容易理解,绝对能使你眼前一亮,通过这篇文章的详细介绍希望你能有所收获。
创新互联是一家专业提供镇江企业网站建设,专注与做网站、成都网站建设、HTML5、小程序制作等业务。10年已为镇江众多企业、政府机构等服务。创新互联专业网络公司优惠进行中。一、创建ModelForm
from django.forms import ModelForm from appxx import models from django.forms import widgets as wdt # 因为重名,所以起个别名 #定义一个类,比如BookForm,这个类要继承ModelForm,在这个类中再写一个原类Meta(规定写法,注意首字母是大写的) #在这个原类中,有以下属性(部分): class BookForm(ModelForm): class Meta: model = models.Book # 对应的Model中的类 fields = "__all__" # 字段,如果是__all__,就表示列出所有的字段,或者使用列表列出想要的字段 exclude = None # 排除的字段 # error_messages用法 error_messages = { "title": {"required": "书名不能为空"}, "price": {"required": "售价不能为空"}, } # widgets用法,比如把输入用户名的input框给为Textarea widgets = { "name": wdt.Textarea(attrs={"class": "c1"}) # 还可以自定义属性 } #labels,自定义在前端显示的名字 labels= { "title": "书名", "price": "售价", }
然后在 url 对应的视图函数中实例化这个类,把这个对象传给前端:
def add_book(request): form = forms.BookForm() return render(request, "add_book.html", {"form": form})
然后在前端像Form组件那样渲染页面
二、添加数据
保存数据的时候,不用挨个取数据了,只需要 save 一下即可。
from django.shortcuts import render,redirect from appxx import models from appxx import forms def add_book(request): if request.method == "POST": form = forms.BookForm(request.POST) if form.is_valid(): form.save() return redirect("/book/") form = forms.BookForm() return render(request, "add_book.html", {"form": form})
三、编辑数据
如果不使用 ModelForm,编辑的时候得显示之前的数据,还得挨个取一遍值;如果使用 ModelForm,只需要加一个instance=obj(obj是要修改的数据库的一条数据的对象)就可以得到同样的效果。
保存的时候要注意,一定要注意有这个对象(instance=obj),否则不知道更新哪一个数据。
from django.shortcuts import render,redirect from appxx import models from appxx import forms def edit_book(request, edit_book_id): edit_book= models.Book.objects.filter(id=edit_book_id).first() if request.method == "POST": form = forms.BookForm(request.POST, instance=edit_book) if form.is_valid(): form.save() return redirect("/book/") form = forms.BookForm(instance=edit_book) return render(request, "edit_book.html", {"form": form})
总结: 从上边可以看到 ModelForm 用起来是非常方便的,比如增加修改之类的操作。但是也带来额外不好的地方,model和form之间耦合了。如果不耦合的话,form.save()方法也无法直接提交保存。 但是耦合的话使用场景通常局限用于小程序,写大程序就最好不用了。
四、完整示例代码
项目结构
urls.py
from django.conf.urls import url from django.contrib import admin from appxx import views urlpatterns = [ url(r'^admin/', admin.site.urls), url(r"^book/$", views.book), url(r"^book/add/", views.add_book), url(r"^book/edit/(\d+)/", views.edit_book), ]
views.py
from django.shortcuts import render,redirect from appxx import models from appxx import forms def book(request): book_list = models.Book.objects.all() return render(request, "book.html", {"book_list": book_list}) def add_book(request): if request.method == "POST": form = forms.BookForm(request.POST) if form.is_valid(): form.save() return redirect("/book/") form = forms.BookForm() return render(request, "add_book.html", {"form": form}) def edit_book(request, edit_book_id): edit_book= models.Book.objects.filter(id=edit_book_id).first() if request.method == "POST": form = forms.BookForm(request.POST, instance=edit_book) if form.is_valid(): form.save() return redirect("/book/") form = forms.BookForm(instance=edit_book) return render(request, "edit_book.html", {"form": form})
models.py
from django.db import models class Book(models.Model): id = models.AutoField(primary_key=True) title = models.CharField(max_length=32) price = models.DecimalField(max_digits=5, decimal_places=2) publish_date = models.DateField() publisher = models.ForeignKey(to="Publisher") authors = models.ManyToManyField(to="Author") def __str__(self): return self.title class Publisher(models.Model): id = models.AutoField(primary_key=True) name = models.CharField(max_length=32) def __str__(self): return self.name class Author(models.Model): id = models.AutoField(primary_key=True) name = models.CharField(max_length=32) def __str__(self): return self.name
forms.py
from django.forms import ModelForm from appxx import models from django.forms import widgets as wdt class BookForm(ModelForm): class Meta: model = models.Book fields = "__all__" labels = { "title": "书名", "price": "售价", "publish_date": "出版日期", "publisher": "出版社", "authors": "作者" } widgets = { "title": wdt.TextInput(attrs={"class": "form-control"}), "price": wdt.TextInput(attrs={"class": "form-control"}), "publish_date": wdt.TextInput(attrs={"class": "form-control", "type": "date"}), "publisher": wdt.Select(attrs={"class": "form-control"}), "authors": wdt.SelectMultiple(attrs={"class": "form-control"}), } error_messages = { "title": {"required": "书名不能为空"}, "price": {"required": "售价不能为空"}, "publish_date": {"required": "出版日期不能为空"}, "publisher": {"required": "出版社不能为空"}, "authors": {"required": "作者不能为空"}, }
book.html
展示书籍
add_book.html和edit_book.html(两个页面代码一样)
添加书籍 {# panel开始 #}{# panel结束 #}{# panel-body开始 #}添加书籍
{# form开始 #} {# form结束 #}{# panel-body结束 #}
上述内容就是ModelForm组件怎么在Django中使用,你们学到知识或技能了吗?如果还想学到更多技能或者丰富自己的知识储备,欢迎关注创新互联行业资讯频道。
文章标题:ModelForm组件怎么在Django中使用-创新互联
本文链接:http://scyanting.com/article/ccjcoc.html