32)django-modelform

一：mdoelform

　　modelform是model和form结合

　　model+form =>验证+数据库

class A(model):
    user=
    pass=

Form:
    class LoginForm(model):
        user=
        pass=
字段重复

modelform

    class LoginModelForm(XXX)
        利用model.A中字段

二：modelfrom写法

class UserInfoModelForm(forms.ModelForm):
    class Meta:
        model=models.UserInfo #去那个类里获取字段
        fields="__all__" #__all__代自所有字段， fields=["username",",email"]
        exclude=["username"] #除了username字段之外

继承顺序：
UserInfoForm-->Form-->BaseForm
UserInfoModelForm--ModelForm--BaseModelForm-->BaseForm

三：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={...})

四：示例

　　1）快速生成表单和编辑

  #urls.py

    url(r'^index/', views.index),
    url(r'^user_list/', views.user_list),
    url(r'^edit-(\d+)/', views.user_edit),

   #views.py
from django.shortcuts import render,HttpResponse
from app01 import models

from django import forms
from django.forms import fields as Ffields
from django.forms import widgets as Fwidgets
class UserInfoModelForm(forms.ModelForm):

    is_rmb = Ffields.CharField(widget=Fwidgets.CheckboxInput())

    class Meta:
        model = models.UserInfo
        fields = '__all__'
        # fields =  ['username','email']
        # exclude = ['username']
        labels = {
            'username': '用户名',
            'email': '邮箱',
        }
        help_texts = {
            'username': '...'
        }
        widgets = {
            'username': Fwidgets.Textarea(attrs={'class': 'c1'})
        }
        error_messages = {
            '__all__':{

            },
            'email': {
                'required': '邮箱不能为空',
                'invalid': '邮箱格式错误..',
            }
        }
        field_classes = {
            # 'email': Ffields.URLField
        }

        # localized_fields=('ctime',)

    def clean_username(self):
        old = self.cleaned_data['username']
        return old

class UserInfoForm(forms.Form):
    username = Ffields.CharField(max_length=32)
    email = Ffields.EmailField()
    user_type = Ffields.ChoiceField(
        choices=models.UserType.objects.values_list('id','caption')
    )

    def __init__(self, *args, **kwargs):
        super(UserInfoForm,self).__init__(*args, **kwargs)
        self.fields['user_type'].choices = models.UserType.objects.values_list('id','caption')

def index(request):
    if request.method == "GET":
        obj = UserInfoModelForm()
        return render(request,'index.html',{'obj': obj})
    elif request.method == "POST":
        obj = UserInfoModelForm(request.POST)
        if obj.is_valid():
            # obj.save()
            instance = obj.save(False)
            instance.save()
            obj.save_m2m()

        # print(obj.is_valid())
        # print(obj.cleaned_data)
        # print(obj.errors.as_json())
        return render(request,'index.html',{'obj': obj})

def user_list(request):
    li = models.UserInfo.objects.all().select_related('user_type')
    return render(request,'user_list.html',{'li': li})

def user_edit(request, nid):
    # 获取当前id对象的用户信息
    # 显示用户已经存在数据
    if request.method == "GET":
        user_obj = models.UserInfo.objects.filter(id=nid).first()
        mf = UserInfoModelForm(instance=user_obj)
        return render(request,'user_edit.html',{'mf': mf, 'nid': nid})
    elif request.method == 'POST':
        user_obj = models.UserInfo.objects.filter(id=nid).first()
        mf = UserInfoModelForm(request.POST,instance=user_obj)
        if mf.is_valid():

            mf.save()
        else:
            print(mf.errors.as_json())
        return render(request,'user_edit.html',{'mf': mf, 'nid': nid})

#index.htm 快速生成表单
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title></title>
</head>
<body>
    <form action="/index/" method="POST">
        {% csrf_token %}
        {{ obj.as_p }}
        <input type="submit" value="提交" />
    </form>
</body>
</html>

#user_list.html #用户列表
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title></title>
</head>
<body>
        <ul>
            {% for row in li %}
                <li>{{ row.username }} - {{ row.user_type.caption }} - <a href="/edit-{{ row.id }}/">编辑</a></li>
            {% endfor %}
        </ul>
</body>
</html>

#user_edit.html #快递编辑
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title></title>
</head>
<body>
    <form method="POST" action="/edit-{{ nid }}/">
        {% csrf_token %}
    {{ mf.as_p }}
        <input type="submit" value="提交" />
    </form>

</body>
</html>

　

from django.db import models

# Create your models here.

class UserType(models.Model):
    caption = models.CharField(max_length=32)

class UserGroup(models.Model):
    name = models.CharField(max_length=32)

class UserInfo(models.Model):
    username = models.CharField(max_length=32)
    email = models.EmailField()
    user_type = models.ForeignKey(to='UserType',to_field='id')
    u2g = models.ManyToManyField(UserGroup)