Django之ModelForm
阿新 • • 發佈：2018-04-22
分支 小型 RM ted per require AS 截取 字典 
ModelForm：
應用場景：
- ModelForm - 中小型應用程序。因為ModelForm是依賴於models的
- Form - 大型應用程序 *
1 ModelForm 2 a. class Meta: 3 model, # 對應Model的 4 fields=None, # 字段 5 exclude=None, #排除字段 6 labels=None, # 提示信息 7 help_texts=None, # 幫助提示信息 8 widgets=None, # 自定義插件 9 error_messages=None, # 自定義錯誤信息（整體錯誤信息from django.core.exceptions import NON_FIELD_ERRORS） 10 field_classes=None #自定義字段類 （也可以自定義字段） 11 localized_fields=(‘birth_date‘,) # 本地化，如：根據不同時區顯示數據 12 如： 13 數據庫中 14 2016-12-27 04:10:57 15 setting中的配置 16 TIME_ZONE = ‘Asia/Shanghai‘ 17 USE_TZ = True 18 則顯示：19 2016-12-27 12:10:57 20 b. 驗證執行過程 21 is_valid -> full_clean -> 鉤子 -> 整體錯誤 22 23 c. 字典字段驗證 24 def clean_字段名(self): 25 # 可以拋出異常 26 # from django.core.exceptions import ValidationError 27 return "新值" 28 d. 用於驗證 29 model_form_obj = XXOOModelForm() 30 model_form_obj.is_valid() 31 model_form_obj.errors.as_json() 32 model_form_obj.clean() 33 model_form_obj.cleaned_data 34 e. 用於創建 35 model_form_obj = XXOOModelForm(request.POST) 36 #### 頁面顯示，並提交 ##### 37 # 默認保存多對多 38 obj = form.save(commit=True) 39 # 不做任何操作，內部定義 save_m2m（用於保存多對多） 40 obj = form.save(commit=False) 41 obj.save() # 保存單表信息 42 obj.save_m2m() # 保存關聯多對多信息 43 44 f. 用於更新和初始化 45 obj = model.tb.objects.get(id=1) 46 model_form_obj = XXOOModelForm(request.POST,instance=obj) 47 ... 48 49 PS: 單純初始化 50 model_form_obj = XXOOModelForm(initial={...})
1 - 1. 類 2 class Foo(ModelForm): 3 class Meta: 4 # model = models.Role 5 # fields = "__all__" 6 # fields = [‘caption‘,] 7 # exclude = [‘catpion‘] 8 model = models.UserType 9 fields = "__all__" 10 11 error_messages = { 12 ‘title‘:{‘required‘:‘名稱不能為空‘,‘invalid‘:‘格式錯誤‘} 13 } 14 widgets = { 15 ‘title‘:wd.TextInput(attrs={‘class‘:‘c1‘}) 16 } 17 18 - 2. 添加 19 GET: 20 form = Foo() 21 POST: 22 form = Foo(data=request.POST) 23 form.is_valid() 24 form.cleaned_data 25 form.erros 26 form.save() 27 - 3. 修改 28 GET: 29 form = Foo(instance=obj) 30 31 POST: 32 form = Foo(instance=obj,dat=request.POST) 33 ... 34 form.save()註意
使用
1 from django.shortcuts import render,HttpResponse 2 from app01 import models 3 4 from django import forms 5 from django.forms import fields as Ffields 6 from django.forms import widgets as Fwidgets 7 class UserInfoModelForm(forms.ModelForm): 8 9 is_rmb = Ffields.CharField(widget=Fwidgets.CheckboxInput()) # 免登錄Checkbox字段 10 11 class Meta: 12 model = models.UserInfo 13 fields = ‘__all__‘ 14 # fields = [‘username‘,‘email‘] 15 # exclude = [‘username‘] 16 labels = { 17 ‘username‘: ‘用戶名‘, 18 ‘email‘: ‘郵箱‘, 19 } 20 help_texts = { 21 ‘username‘: ‘...‘ 22 } 23 widgets = { 24 ‘username‘: Fwidgets.Textarea(attrs={‘class‘: ‘c1‘}) 25 } 26 error_messages = { 27 ‘__all__‘:{ # 定義整體的錯誤信息 28 29 }, 30 ‘email‘: { 31 ‘required‘: ‘郵箱不能為空‘, 32 ‘invalid‘: ‘郵箱格式錯誤..‘, 33 } 34 } 35 field_classes = { 36 # ‘email‘: Ffields.URLField # 和model中定義字段不同，這裏只能填寫類，可以覆蓋model中的字段屬性 37 } 38 39 # localized_fields=(‘ctime‘,) 40 41 def clean_username(self): 42 old = self.cleaned_data[‘username‘] 43 return old 44 45 class UserInfoForm(forms.Form): 46 username = Ffields.CharField(max_length=32) 47 email = Ffields.EmailField() 48 user_type = Ffields.ChoiceField( 49 choices=models.UserType.objects.values_list(‘id‘,‘caption‘) 50 ) 51 52 def __init__(self, *args, **kwargs): 53 super(UserInfoForm,self).__init__(*args, **kwargs) 54 self.fields[‘user_type‘].choices = models.UserType.objects.values_list(‘id‘,‘caption‘) 55 ‘‘‘ 56 源碼截取： 57 def save(self, commit=True): 58 if commit: 59 # If committing, save the instance and the m2m data immediately. 60 self.instance.save() 61 self._save_m2m() 62 else: 63 # If not committing, add a method to the form to allow deferred 64 # saving of m2m data. 65 self.save_m2m = self._save_m2m 66 ‘‘‘ 67 68 def index(request): 69 if request.method == "GET": 70 obj = UserInfoModelForm() 71 return render(request,‘index.html‘,{‘obj‘: obj}) 72 elif request.method == "POST": 73 obj = UserInfoModelForm(request.POST) 74 if obj.is_valid(): 75 # obj.save() 76 instance = obj.save(False) # self.instance 當前model對象 77 instance.save() # 僅保存當前類對應的表,相當於源碼中if條件的self.instance.save() 78 obj.save_m2m() # 相當於源碼中if條件的self._save_m2m()，else分支中做了賦值self.save_m2m = self._save_m2m 79 80 81 # print(obj.is_valid()) 82 # print(obj.cleaned_data) 83 # print(obj.errors.as_json()) 84 return render(request,‘index.html‘,{‘obj‘: obj}) 85 86 87 def user_list(request): 88 li = models.UserInfo.objects.all().select_related(‘user_type‘) 89 return render(request,‘user_list.html‘,{‘li‘: li}) 90 91 def user_edit(request, nid): 92 # 獲取當前id對象的用戶信息 93 94 if request.method == "GET": 95 user_obj = models.UserInfo.objects.filter(id=nid).first() 96 mf = UserInfoModelForm(instance=user_obj) # 顯示用戶已經存在數據 97 return render(request,‘user_edit.html‘,{‘mf‘: mf, ‘nid‘: nid}) 98 elif request.method == ‘POST‘: 99 user_obj = models.UserInfo.objects.filter(id=nid).first() 100 mf = UserInfoModelForm(request.POST,instance=user_obj) 101 if mf.is_valid(): 102 103 mf.save() 104 else: 105 print(mf.errors.as_json()) 106 return render(request,‘user_edit.html‘,{‘mf‘: mf, ‘nid‘: nid}) 107 108 # modelform小結 109 1. 生成HTML標簽：class Meta: ... 110 2. 顯示用戶已經存在數據 ：mf = xxxModelForm(instance=ModelObj) 111 3. 額外的標簽， is_rmb = Ffields.CharField(widget=Fwidgets.CheckboxInput()) # 7天免登錄Checkbox字段 112 4. 各種驗證 is_valid() -> 各種鉤子... # 方法和Form中的鉤子完全一樣 113 5. mf.save() 114 # 或 115 instance = mf.save(False) 116 instance.save() 117 mf.save_m2m()
Django之ModelForm