Django-ModelForm

ModelForm

 顾名思义就是讲model和form结合起来啦。原来用form组件的时候。form和model分开,我们在使用form组件 的时候还要创建自己的字段,现在modelform直接可以用model里面的数据啦。

废话不说 直接看代码

from django.db import models


# Create your models here.
class Author(models.Model):
    nid = models.AutoField(primary_key=True)
    name = models.CharField(max_length=32)
    age = models.IntegerField()
    email=models.EmailField(max_length=32)
    # 与AuthorDetail建立一对一的关系

    def __str__(self):
        return self.name


class Publish(models.Model):
    nid = models.AutoField(primary_key=True)
    name = models.CharField(max_length=32)
    city = models.CharField(max_length=32)
    email = models.EmailField()


    def __str__(self):
        return self.name



class Book(models.Model):
    nid = models.AutoField(primary_key=True)
    title = models.CharField(max_length=32)
    publishDate = models.DateTimeField()
    price = models.DecimalField(max_digits=5, decimal_places=2)
    # 与Publish建立一对多的关系,外键字段建立在多的一方
    publish = models.ForeignKey(to="Publish", to_field="nid")
    # 与Author表建立多对多的关系,ManyToManyField可以建在两个模型中的任意一个,自动创建第三张表
    authors = models.ManyToManyField(to='Author')


    def __str__(self):
        return self.title
model
from django.forms import ModelForm,widgets as wd,fields
from app01 import  models
class BookModelForm(ModelForm):
    class Meta:
        model=models.Book
        fields="__all__"
        #如果不想用全部字段直接选取自己需要的字段即可
        #files=["title","price,"authors"]

        error_messages={
            'title':{"required":"书名不能为空"},
            'price':{"invilid":"价格只能是数字"}
        }

        #一般不指定默认就有
        widgets={
            'title':wd.TextInput(attrs=({"id":"title"})),
            'price':wd.TextInput(attrs={"id":"price"}),
            'publish':wd.Select(attrs={"id":"publish"}),

        }

        labels={
            "title":"书名",
            'publishDate':'出版日期',
            'publish':'出版社',
            'price':'价格',
            'authors':'作者'
        }

        #当然还有钩子函数
forms
from django.shortcuts import render,redirect,HttpResponse
from app01 import  models
from app01.forms import BookModelForm
# Create your views here.
def index(request):
    books=models.Book.objects.all()
    return render(request,"index.html",{"books":books})
def addBook(request):
    if request.method=="POST":
        form=BookModelForm(request.POST)
        print(form)
        if form.is_valid():
            form.save()

            return redirect("/index/")
        print(form.errors)
        return render(request,"addBook.html",{"form":form})
    form =BookModelForm()
    return render(request,"addBook.html",{"form":form})

def editBook(request,id):
    book=models.Book.objects.filter(nid=id).first()
    if not  book:
        return HttpResponse("eror")
    else:
        if request.method=="POST":
            form=BookModelForm(instance=book,data=request.POST)
            if form .is_valid():
                form.save()
                return redirect("/index/")
        else:
            form=BookModelForm(instance=book)
            return render(request,"editBook.html",{"form":form,"id":id})
Views
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>Title</title>
    <link rel="stylesheet" href="/static/bootstrap-3.3.7-dist/css/bootstrap.min.css">
</head>
<body>
 <div class="table-responsive table-bordered">
                <table id="t1" class="table table-striped table-bordered">
                    <thead>
                    <tr>
                        <th>编号</th>
                        <th>书名</th>
                        <th>出版日期</th>
                        <th>价格</th>
                        <th>出版社</th>
                        <th>作者</th>
                        <th>操作</th>
                    </tr>
                    </thead>
                    <tbody>
                    {% for book in books %}
                        <tr>
                            <td class="hide">{{ book.nid }}</td>
                            <td>{{ forloop.counter }}</td>
                            <td>{{ book.title }}</td>
                            <td>{{ book.publishDate|date:"Y-m-d " }}</td>
                            <td>{{ book.price }}</td>
                            <td>{{ book.publish }}</td>
                            <td >
                             {% for author in book.authors.all %}
                                {{ author.name }}
                             {% endfor %}

                            </td>
                            <td>


                                 <a href="/editBook/{{ book.nid }}/">
                                    <button class="btn btn-warning">编辑</button>
                                </a>



                            <a href="/delBook/{{ book.id }}/">
                                    <button class="btn btn-danger del">删除</button>
                                </a>



                            </td>
                        </tr>

                    {% endfor %}

                    </tbody>
                </table>
            </div>
</body>
</html>
index.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>Title</title>
</head>
<body>
<form action="/editBook/{{ id }}/" method="post">
    {% csrf_token %}
    {{ form.as_p }}
    <p><input type="submit"></p>
    </form>
</body>
</html>
editBook.html
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>Title</title>
</head>
<body>
<form action="/addBook/" method="post">
    {% csrf_token %}
<div>书名{{ form.title }}{{ form.errors.title.0 }}</div>
<div>出版日期{{ form.publishDate }}{{ form.errors.publishDate.0 }}</div>
<div>jiage{{ form.price }}{{ form.errors.price.0 }}</div>
<div>出版设{{ form.publish }}</div>
<div>作者{{ form.authors }}</div>
    <p><input type="submit"></p>
    </form>
</body>
</html>
addBook.html

注意:导入模块名(fields、widgets)和字段名重复,所以导入时要起个别名。具体见上面代码

modelform相关知识

自定制字段名

如何定义http上定义的字段呢,自定义写成中文的?之前的用法是在Form里写上label。Model Form定义要用verbose_name

models.py

class UserInfo(models.Model):
    username = models.CharField(max_length=32, verbose_name='用户')
    email = models.EmailField(verbose_name='邮箱')
    user_type = models.ForeignKey(to='UserType',to_field='id', verbose_name='类型')
View Code

如果不在model里定义,在modelForm里实现,利用labels

class UserInfoModelForm(forms.ModelForm):

    class Meta:
        model = models.UserInfo
        fields = "__all__"
        labels = {
            'username':'用户名',
            'email':'邮箱',
        }

展示指定的列

fields = "__all__"上面展示所有的,可不可以展示指定的列

 fields = ['username','email']   # 显示指定列
        exclude = ['username']          # 排除指定列

为什么modelForm里也能做验证?

form里面有is_validcleaned_dataerrors

# Form验证:
    UserInfoForm -> Form -> BaseForm( 包含is_valid等方法)

# ModelForm验证:
    UserInfoModelForm -> ModelForm -> BaseModelForm -> BaseForm

ModelForm组件

ModelForm
    a.  class Meta:
            model,                           # 对应Model的
            fields=None,                     # 字段
            exclude=None,                    # 排除字段
            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(整体错误信息from django.core.exceptions import NON_FIELD_ERRORS)
            field_classes=None               # 自定义字段类 (也可以自定义字段)
            localized_fields=('birth_date',) # 本地化,如:根据不同时区显示数据
            如:
                数据库中
                    2016-12-27 04:10:57
                setting中的配置
                    TIME_ZONE = 'Asia/Shanghai'
                    USE_TZ = True
                则显示:
                    2016-12-27 12:10:57
    b. 验证执行过程
        is_valid -> full_clean -> 钩子 -> 整体错误

    c. 字典字段验证
        def clean_字段名(self):
            # 可以抛出异常
            # from django.core.exceptions import ValidationError
            return "新值"
    d. 用于验证
        model_form_obj = XXOOModelForm()
        model_form_obj.is_valid()
        model_form_obj.errors.as_json()
        model_form_obj.clean()
        model_form_obj.cleaned_data
    e. 用于创建
        model_form_obj = XXOOModelForm(request.POST)
        #### 页面显示,并提交 #####
        # 默认保存多对多
            obj = form.save(commit=True)
        # 不做任何操作,内部定义 save_m2m(用于保存多对多)
            obj = form.save(commit=False)
            obj.save()      # 保存单表信息
            obj.save_m2m()  # 保存关联多对多信息

    f. 用于更新和初始化
        obj = model.tb.objects.get(id=1)
        model_form_obj = XXOOModelForm(request.POST,instance=obj)
        ...

        PS: 单纯初始化
            model_form_obj = XXOOModelForm(initial={...})

  

- Model Form
    
        应用场景:
            - ModelForm - 中小型应用程序
            - Form      - 大型应用程序  *
        注意事项:
            - 1. 类 
                  class Foo(ModelForm):
                    class Meta:
                        # model = models.Role
                        # fields = "__all__"
                        # fields = ['caption',]
                        # exclude = ['catpion']
                        model = models.UserType
                        fields = "__all__"

                        error_messages = {
                            'title':{'required':'名称不能为空','invalid':'格式错误'}
                        }
                        widgets = {
                            'title':wd.TextInput(attrs={'class':'c1'})
                        }
                
            - 2. 添加
                 GET:
                    form = Foo()
                 POST:
                    form = Foo(data=request.POST)
                    form.is_valid()
                    form.cleaned_data
                    form.erros
                    form.save()
            - 3. 修改
                 GET:
                    form = Foo(instance=obj)
                 
                 POST:
                    form = Foo(instance=obj,dat=request.POST)
                    ...
                    form.save()
                    
原文地址:https://www.cnblogs.com/ctztake/p/7995493.html