Django之Modelform组件

Modelform组件

Modelform就是model和from两者结合起来的。它既有验证，又有数据库的操作

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={...})

Modelform注意事项：

1、类

  class Foo(ModelFrom):
       class Meta:
            model=models.Role
            #fields="__all__"         所有的字段
            #fields=['caption',]      只取caption这个字段
            #xclude=['caption']       除caption这个字段外不取，剩余的都取
            error_massages={
                           '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(instaance=obj,data=request.POST)
     form.save()
     

示列(增删改查)：

url:

from django.conf.urls import url
from django.contrib import admin
from app01 import views
urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'^role/$', views.role),
    url(r'^role/add/$', views.role_add),
    url(r'^role/edit/(d+)/$', views.role_edit),
    url(r'^usertype/$', views.user_type),
    url(r'^usertype/add/$', views.user_type_add),
    url(r'^usertype/edit/(d+)/$', views.user_type_edit),
    #url(r'^role.html$', admin.site.urls),
]

views:

from django.shortcuts import render,redirect,HttpResponse
from app01 import models


from django.forms import Form,ModelForm
from django.forms import fields
from django.forms import widgets as wd




def role(request):
    roles = models.Role.objects.all()
    return render(request,'role.html',{'roles':roles})


class Role(ModelForm):

    class Meta:
        model = models.Role
        fields = "__all__"


def role_add(request):
    if request.method == "GET":
        form = Role()
        return render(request,'role_add.html',{'form':form})
    else:
        form = Role(request.POST)
        if form.is_valid():
            form.save()
            # models.Role.objects.create(**form.cleaned_data)
            # models.Role.objects.create(**{'catpion':'123'})
            return redirect('/role/')
        else:
            return render(request, 'role_add.html', {'form': form})


def role_edit(request,nid):
    obj = models.Role.objects.filter(id=nid).first()
    if not obj:
        return HttpResponse('数据不存在')

    if request.method == "GET":
        form = Role(instance=obj)
        return render(request,'role_edit.html',{'form':form})
    else:
        form = Role(data=request.POST,instance=obj)
        if form.is_valid():
            form.save()
            return redirect('/role/')
        else:
            return render(request, 'role_edit.html', {'form': form})


def user_type(request):
    user_type_list = models.UserType.objects.all()
    return render(request,'user_type.html',{'user_type_list':user_type_list})

class UserTypeModeForm(ModelForm):
    title = fields.CharField(max_length=6,required=True,widget=wd.Textarea())

    class Meta:
        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'})
        }

    # 钩子函数

def user_type_add(request):
    if request.method == "GET":
        form = UserTypeModeForm()
        return render(request,'user_type_add.html',{'form':form})
    else:
        form = UserTypeModeForm(request.POST)
        if form.is_valid():
            form.save()
            return redirect('/usertype/')
        else:
            return render(request, 'user_type_add.html', {'form': form})


def user_type_edit(request,nid):
    obj = models.UserType.objects.filter(id=nid).first()
    if not obj:
        return HttpResponse('...')

    if request.method == 'GET':
        # 显示默认值
        form = UserTypeModeForm(instance=obj)
        return render(request,'user_type_edit.html',{'form':form})
    else:
        form = UserTypeModeForm(instance=obj,data=request.POST)
        if form.is_valid():
            form.save()
            return redirect('/usertype/')
        else:
            return render(request, 'user_type_edit.html', {'form': form})

role.html:

</head>
<body>
    <ul>
        {% for row in roles %}
            <li>{{ row.caption }}</li>
        {% endfor %}
    </ul>
</body>
</html>

role_add.html:

<body>
    <form method="post">
        {% csrf_token %}
        <p>{{ form.caption }} {{ form.errors.caption.0 }}</p>
        <input type="submit" value="提交">
    </form>
</body>

role_edit.html:

<body>
    <form method="post">
        {% csrf_token %}
        <p>{{ form.caption }} {{ form.errors.caption.0 }}</p>
        <input type="submit" value="提交">
    </form>
</body>

user_type.html

<body>
    <ul>
        {% for row in user_type_list %}
            <li>{{ row.title }} - {{ row.roles.all }}</li>
        {% endfor %}
    </ul>
</body>

user_type_add.html

<body>
    <form method="post">
        {% csrf_token %}
        {{ form.as_p }}
        <input type="submit" value="提交">
    </form>
</body>

user_type_edit.html

<body>
    <form method="post" novalidate>
        {% csrf_token %}
        {{ form.as_p }}
        <input type="submit" value="提交">
    </form>
</body>