第八章
Posted hanwei999
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- 元信息
- 多表关系
- 反向查找
- ORM操作
- 进阶操作
- 其它操作
- 高效率关联表
- models自带验证
- models内置钩子
- from,choices
- Form类
- From内置钩子验证
- obj.is_valid()错误信息
1,元信息
class UserInfo(models.Model): nid = models.AutoField(primary_key=True) username = models.CharField(max_length=32) class Meta: # 数据库中生成的表名称 默认 app名称 + 下划线 + 类名 db_table = "table_name" # 联合索引 index_together = [ ("pub_date", "deadline"), ] # 联合唯一索引 unique_together = (("driver", "restaurant"),) # admin中显示的表名称 verbose_name # verbose_name加s verbose_name_plural #最前缀的模式 select * from where name=‘xxx‘ select * from where name=‘xxx‘ and email=‘xx‘ select * from where email=‘xx‘ 无法命中 unique_together = (("driver","restaurant"),)
https://www.cnblogs.com/wupeiqi/articles/6216618.html
2,多表关系
ForeignKey(ForeignObject) # ForeignObject(RelatedField) to, # 要进行关联的表名 to_field=None, # 要关联的表中的字段名称 on_delete=None, # 当删除关联表中的数据时,当前表与其关联的行的行为 - models.CASCADE,删除关联数据,与之关联也删除 - models.DO_NOTHING,删除关联数据,引发错误IntegrityError - models.PROTECT,删除关联数据,引发错误ProtectedError - models.SET_NULL,删除关联数据,与之关联的值设置为null(前提FK字段需要设置为可空) - models.SET_DEFAULT,删除关联数据,与之关联的值设置为默认值(前提FK字段需要设置默认值) - models.SET,删除关联数据, a. 与之关联的值设置为指定值,设置:models.SET(值) b. 与之关联的值设置为可执行对象的返回值,设置:models.SET(可执行对象) def func(): return 10 class MyModel(models.Model): user = models.ForeignKey( to="User", to_field="id" on_delete=models.SET(func),) related_name=None, # 反向操作时,使用的字段名,用于代替 【表名_set】 如: obj.表名_set.all() related_query_name=None, # 反向操作时,使用的连接前缀,用于替换【表名】 如: models.UserGroup.objects.filter(表名__字段名=1).values(‘表名__字段名‘) limit_choices_to=None, # 在Admin或ModelForm中显示关联数据时,提供的条件: # 如: - limit_choices_to={‘nid__gt‘: 5} - limit_choices_to=lambda : {‘nid__gt‘: 5} from django.db.models import Q - limit_choices_to=Q(nid__gt=10) - limit_choices_to=Q(nid=8) | Q(nid__gt=10) - limit_choices_to=lambda : Q(Q(nid=8) | Q(nid__gt=10)) & Q(caption=‘root‘) db_constraint=True # 是否在数据库中创建外键约束 parent_link=False # 在Admin中是否显示关联数据 OneToOneField(ForeignKey) to, # 要进行关联的表名 to_field=None # 要关联的表中的字段名称 on_delete=None, # 当删除关联表中的数据时,当前表与其关联的行的行为 ###### 对于一对一 ###### # 1. 一对一其实就是 一对多 + 唯一索引 # 2.当两个类之间有继承关系时,默认会创建一个一对一字段 # 如下会在A表中额外增加一个c_ptr_id列且唯一: class C(models.Model): nid = models.AutoField(primary_key=True) part = models.CharField(max_length=12) class A(C): id = models.AutoField(primary_key=True) code = models.CharField(max_length=1) ManyToManyField(RelatedField) to, # 要进行关联的表名 related_name=None, # 反向操作时,使用的字段名,用于代替 【表名_set】 如: obj.表名_set.all() related_query_name=None, # 反向操作时,使用的连接前缀,用于替换【表名】 如: models.UserGroup.objects.filter(表名__字段名=1).values(‘表名__字段名‘) limit_choices_to=None, # 在Admin或ModelForm中显示关联数据时,提供的条件: # 如: - limit_choices_to={‘nid__gt‘: 5} - limit_choices_to=lambda : {‘nid__gt‘: 5} from django.db.models import Q - limit_choices_to=Q(nid__gt=10) - limit_choices_to=Q(nid=8) | Q(nid__gt=10) - limit_choices_to=lambda : Q(Q(nid=8) | Q(nid__gt=10)) & Q(caption=‘root‘) symmetrical=None, # 仅用于多对多自关联时,symmetrical用于指定内部是否创建反向操作的字段 # 做如下操作时,不同的symmetrical会有不同的可选字段 models.BB.objects.filter(...) # 可选字段有:code, id, m1 class BB(models.Model): code = models.CharField(max_length=12) m1 = models.ManyToManyField(‘self‘,symmetrical=True) # 可选字段有: bb, code, id, m1 class BB(models.Model): code = models.CharField(max_length=12) m1 = models.ManyToManyField(‘self‘,symmetrical=False) through=None, # 自定义第三张表时,使用字段用于指定关系表 through_fields=None, # 自定义第三张表时,使用字段用于指定关系表中那些字段做多对多关系表 from django.db import models class Person(models.Model): name = models.CharField(max_length=50) class Group(models.Model): name = models.CharField(max_length=128) members = models.ManyToManyField( Person, through=‘Membership‘, through_fields=(‘group‘, ‘person‘), ) class Membership(models.Model): group = models.ForeignKey(Group, on_delete=models.CASCADE) person = models.ForeignKey(Person, on_delete=models.CASCADE) inviter = models.ForeignKey( Person, on_delete=models.CASCADE, related_name="membership_invites", ) invite_reason = models.CharField(max_length=64) db_constraint=True, # 是否在数据库中创建外键约束 db_table=None, # 默认创建第三张表时,数据库中表的名称
3,反向操作
from django db import models class UserType(models.Model): name = models.CharField(max_length=32) class User(models.Model): user = models.CharField(max_length=64) pwd = models.CharField(max_length=64) ut = models.FareignKey(to=‘UserType‘,to_field=‘id‘) v = User.objects.all() for item in v: item.user item.pwd item.ut.name User.objects.all().values(‘user‘,‘ut_name‘) ### v = UserType.objects.all() for item in v: item.name item.id item.user_set.all() UserType.objects.all().values(‘name‘,‘user_set‘)
4,ORM操作
# 增 # # models.Tb1.objects.create(c1=‘xx‘, c2=‘oo‘) 增加一条数据,可以接受字典类型数据 **kwargs # obj = models.Tb1(c1=‘xx‘, c2=‘oo‘) # obj.save() # 查 # # models.Tb1.objects.get(id=123) # 获取单条数据,不存在则报错(不建议) # models.Tb1.objects.all() # 获取全部 # models.Tb1.objects.filter(name=‘seven‘) # 获取指定条件的数据 # models.Tb1.objects.exclude(name=‘seven‘) # 获取指定条件的数据 # 删 # # models.Tb1.objects.filter(name=‘seven‘).delete() # 删除指定条件的数据 # 改 # models.Tb1.objects.filter(name=‘seven‘).update(gender=‘0‘) # 将指定条件的数据更新,均支持 **kwargs # obj = models.Tb1.objects.get(id=1) # obj.c1 = ‘111‘ # obj.save() # 修改单条数据基本操作
5,进阶操作
# 获取个数 # # models.Tb1.objects.filter(name=‘seven‘).count() # 大于,小于 # # models.Tb1.objects.filter(id__gt=1) # 获取id大于1的值 # models.Tb1.objects.filter(id__gte=1) # 获取id大于等于1的值 # models.Tb1.objects.filter(id__lt=10) # 获取id小于10的值 # models.Tb1.objects.filter(id__lte=10) # 获取id小于10的值 # models.Tb1.objects.filter(id__lt=10, id__gt=1) # 获取id大于1 且 小于10的值 # in # # models.Tb1.objects.filter(id__in=[11, 22, 33]) # 获取id等于11、22、33的数据 # models.Tb1.objects.exclude(id__in=[11, 22, 33]) # not in # isnull 是否为空 # Entry.objects.filter(pub_date__isnull=True) # contains (like) # # models.Tb1.objects.filter(name__contains="ven") # models.Tb1.objects.filter(name__icontains="ven") # icontains大小写不敏感 # models.Tb1.objects.exclude(name__icontains="ven") # range 范围 # # models.Tb1.objects.filter(id__range=[1, 2]) # 范围bettwen and # 其他类似 xxx开头 xx结尾 # # startswith,istartswith, endswith, iendswith, # order by 排序 # # models.Tb1.objects.filter(name=‘seven‘).order_by(‘id‘) # asc 正向排序 # models.Tb1.objects.filter(name=‘seven‘).order_by(‘-id‘) # desc 逆向排序 # group by 分组 统计 # # from django.db.models import Count, Min, Max, Sum # models.Tb1.objects.filter(c1=1).values(‘id‘).annotate(c=Count(‘num‘)) # SELECT "app01_tb1"."id", COUNT("app01_tb1"."num") AS "c" FROM "app01_tb1" WHERE "app01_tb1"."c1" = 1 GROUP BY "app01_tb1"."id" # limit 、offset 分页 # # models.Tb1.objects.all()[10:20] # regex正则匹配,iregex 不区分大小写 # # Entry.objects.get(title__regex=r‘^(An?|The) +‘) # Entry.objects.get(title__iregex=r‘^(an?|the) +‘) 按时间查找 # date # # Entry.objects.filter(pub_date__date=datetime.date(2005, 1, 1)) # Entry.objects.filter(pub_date__date__gt=datetime.date(2005, 1, 1)) # year # # Entry.objects.filter(pub_date__year=2005) # Entry.objects.filter(pub_date__year__gte=2005) # month # # Entry.objects.filter(pub_date__month=12) # Entry.objects.filter(pub_date__month__gte=6) # day # # Entry.objects.filter(pub_date__day=3) # Entry.objects.filter(pub_date__day__gte=3) # week_day # # Entry.objects.filter(pub_date__week_day=2) # Entry.objects.filter(pub_date__week_day__gte=2) # hour # # Event.objects.filter(timestamp__hour=23) # Event.objects.filter(time__hour=5) # Event.objects.filter(timestamp__hour__gte=12) # minute # # Event.objects.filter(timestamp__minute=29) # Event.objects.filter(time__minute=46) # Event.objects.filter(timestamp__minute__gte=29) # second # # Event.objects.filter(timestamp__second=31) # Event.objects.filter(time__second=2) # Event.objects.filter(timestamp__second__gte=31)
6,其他操作
################################################################## # PUBLIC METHODS THAT ALTER ATTRIBUTES AND RETURN A NEW QUERYSET # ################################################################## def all(self) # 获取所有的数据对象 def filter(self, *args, **kwargs) # 条件查询 # 条件可以是:参数,字典,Q def exclude(self, *args, **kwargs) # 条件查询 # 条件可以是:参数,字典,Q def select_related(self, *fields) 性能相关:表之间进行join连表操作,一次性获取关联的数据。 model.tb.objects.all().select_related() model.tb.objects.all().select_related(‘外键字段‘) model.tb.objects.all().select_related(‘外键字段__外键字段‘) def prefetch_related(self, *lookups) 性能相关:多表连表操作时速度会慢,使用其执行多次SQL查询在Python代码中实现连表操作。 # 获取所有用户表 # 获取用户类型表where id in (用户表中的查到的所有用户ID) models.UserInfo.objects.prefetch_related(‘外键字段‘) from django.db.models import Count, Case, When, IntegerField Article.objects.annotate( numviews=Count(Case( When(readership__what_time__lt=treshold, then=1), output_field=CharField(), )) ) students = Student.objects.all().annotate(num_excused_absences=models.Sum( models.Case( models.When(absence__type=‘Excused‘, then=1), default=0, output_field=models.IntegerField() ))) def annotate(self, *args, **kwargs) # 用于实现聚合group by查询 from django.db.models import Count, Avg, Max, Min, Sum v = models.UserInfo.objects.values(‘u_id‘).annotate(uid=Count(‘u_id‘)) # SELECT u_id, COUNT(ui) AS `uid` FROM UserInfo GROUP BY u_id v = models.UserInfo.objects.values(‘u_id‘).annotate(uid=Count(‘u_id‘)).filter(uid__gt=1) # SELECT u_id, COUNT(ui_id) AS `uid` FROM UserInfo GROUP BY u_id having count(u_id) > 1 v = models.UserInfo.objects.values(‘u_id‘).annotate(uid=Count(‘u_id‘,distinct=True)).filter(uid__gt=1) # SELECT u_id, COUNT( DISTINCT ui_id) AS `uid` FROM UserInfo GROUP BY u_id having count(u_id) > 1 def distinct(self, *field_names) # 用于distinct去重 models.UserInfo.objects.values(‘nid‘).distinct() # select distinct nid from userinfo 注:只有在PostgreSQL中才能使用distinct进行去重 def order_by(self, *field_names) # 用于排序 models.UserInfo.objects.all().order_by(‘-id‘,‘age‘) def extra(self, select=None, where=None, params=None, tables=None, order_by=None, select_params=None) # 构造额外的查询条件或者映射,如:子查询 Entry.objects.extra(select={‘new_id‘: "select col from sometable where othercol > %s"}, select_params=(1,)) Entry.objects.extra(where=[‘headline=%s‘], params=[‘Lennon‘]) Entry.objects.extra(where=["foo=‘a‘ OR bar = ‘a‘", "baz = ‘a‘"]) Entry.objects.extra(select={‘new_id‘: "select id from tb where id > %s"}, select_params=(1,), order_by=[‘-nid‘]) def reverse(self): # 倒序 models.UserInfo.objects.all().order_by(‘-nid‘).reverse() # 注:如果存在order_by,reverse则是倒序,如果多个排序则一一倒序 def defer(self, *fields): models.UserInfo.objects.defer(‘username‘,‘id‘) 或 models.UserInfo.objects.filter(...).defer(‘username‘,‘id‘) #映射中排除某列数据 def only(self, *fields): #仅取某个表中的数据 models.UserInfo.objects.only(‘username‘,‘id‘) 或 models.UserInfo.objects.filter(...).only(‘username‘,‘id‘) def using(self, alias): 指定使用的数据库,参数为别名(setting中的设置) ################################################## # PUBLIC METHODS THAT RETURN A QUERYSET SUBCLASS # ################################################## def raw(self, raw_query, params=None, translations=None, using=None): # 执行原生SQL models.UserInfo.objects.raw(‘select * from userinfo‘) # 如果SQL是其他表时,必须将名字设置为当前UserInfo对象的主键列名 models.UserInfo.objects.raw(‘select id as nid from 其他表‘) # 为原生SQL设置参数 models.UserInfo.objects.raw(‘select id as nid from userinfo where nid>%s‘, params=[12,]) # 将获取的到列名转换为指定列名 name_map = {‘first‘: ‘first_name‘, ‘last‘: ‘last_name‘, ‘bd‘: ‘birth_date‘, ‘pk‘: ‘id‘} Person.objects.raw(‘SELECT * FROM some_other_table‘, translations=name_map) # 指定数据库 models.UserInfo.objects.raw(‘select * from userinfo‘, using="default") ################### 原生SQL ################### from django.db import connection, connections cursor = connection.cursor() # cursor = connections[‘default‘].cursor() cursor.execute("""SELECT * from auth_user where id = %s""", [1]) row = cursor.fetchone() # fetchall()/fetchmany(..) def values(self, *fields): # 获取每行数据为字典格式 def values_list(self, *fields, **kwargs): # 获取每行数据为元祖 def dates(self, field_name, kind, order=‘ASC‘): # 根据时间进行某一部分进行去重查找并截取指定内容 # kind只能是:"year"(年), "month"(年-月), "day"(年-月-日) # order只能是:"ASC" "DESC" # 并获取转换后的时间 - year : 年-01-01 - month: 年-月-01 - day : 年-月-日 models.DatePlus.objects.dates(‘ctime‘,‘day‘,‘DESC‘) def datetimes(self, field_name, kind, order=‘ASC‘, tzinfo=None): # 根据时间进行某一部分进行去重查找并截取指定内容,将时间转换为指定时区时间 # kind只能是 "year", "month", "day", "hour", "minute", "second" # order只能是:"ASC" "DESC" # tzinfo时区对象 models.DDD.objects.datetimes(‘ctime‘,‘hour‘,tzinfo=pytz.UTC) models.DDD.objects.datetimes(‘ctime‘,‘hour‘,tzinfo=pytz.timezone(‘Asia/Shanghai‘)) """ pip3 install pytz import pytz pytz.all_timezones pytz.timezone(‘Asia/Shanghai’) """ def none(self): # 空QuerySet对象 #################################### # METHODS THAT DO DATABASE QUERIES # #################################### def aggregate(self, *args, **kwargs): # 聚合函数,获取字典类型聚合结果 from django.db.models import Count, Avg, Max, Min, Sum result = models.UserInfo.objects.aggregate(k=Count(‘u_id‘, distinct=True), n=Count(‘nid‘)) ===> {‘k‘: 3, ‘n‘: 4} def count(self): # 获取个数 def get(self, *args, **kwargs): # 获取单个对象 def create(self, **kwargs): # 创建对象 def bulk_create(self, objs, batch_size=None): # 批量插入 # batch_size表示一次插入的个数 objs = [ models.DDD(name=‘r11‘), models.DDD(name=‘r22‘) ] models.DDD.objects.bulk_create(objs, 10) def get_or_create(self, defaults=None, **kwargs): # 如果存在,则获取,否则,创建 # defaults 指定创建时,其他字段的值 obj, created = models.UserInfo.objects.get_or_create(username=‘root1‘, defaults={‘email‘: ‘1111111‘,‘u_id‘: 2, ‘t_id‘: 2}) def update_or_create(self, defaults=None, **kwargs): # 如果存在,则更新,否则,创建 # defaults 指定创建时或更新时的其他字段 obj, created = models.UserInfo.objects.update_or_create(username=‘root1‘, defaults={‘email‘: ‘1111111‘,‘u_id‘: 2, ‘t_id‘: 1}) def first(self): # 获取第一个 def last(self): # 获取最后一个 def in_bulk(self, id_list=None): # 根据主键ID进行查找 id_list = [11,21,31] models.DDD.objects.in_bulk(id_list) def delete(self): # 删除 def update(self, **kwargs): # 更新 def exists(self): # 是否有结果 其他操作
select id,count(id) from tab1 group by id having count(id) > 15; #Entry 跨表查询 select,where #select Entry.objects.filter().extra(select={‘cid‘: "%s"},select_params=[1]) select * 1 as cid from tab1; Entry.objects.extra(select={‘new_id‘: "select col from sometable where othercol = %s" },select_params=[1]) select * (select name from tab2 where nid = id) as new_id from tab1; Entry.objects.extra(select={‘new_id‘: "func(id)"}) select * (select name from tb2 where nid = id) as new_id from tab1; #where Entry.objects.extra(where=[‘headline=1‘,‘nid>1‘]) Entry.objects.extra(where=[‘headline=1 or nid=1‘]) Entry.objects.extra(where=[‘func(ctime)=1 or nid=1‘],params=[])
7,高效率关联表
select_related users = models.User.objects.all().select_related(‘ut‘) for row in users: print(row.user,row.pwd,row.ut_id) print(row.ut.name) print(row.tu.name) #再发一次SQL请求 prefetch_related users = models.User.objects.filter(id_gt=30).prefetch_related(‘ut‘,‘tu‘) select * from users where id > 30 select * from user_type where id in [1,2] for row in users: print(row.user,row.pwd,row.ut_id) print(row.ut.name)
8,models自带验证
obj = models.UserInfo(name=‘alex‘,email=‘alex‘) obj.full_clean() obj.save() return HttpResponse(‘index‘)
9,models内置钩子
class UserInfo(models.Model): name = models.CharField(max_length=32) c = UserInfo.objects.filter(name=self.name).count() if c: raise ValidationError(message=‘用户名已经存在‘,code=‘li‘) ############## from django.forms import vidgets class UserInForm(forms.Form): user = fields.CharField( required=False, widget=widgets.Textarea(attrs={‘class‘:‘c1‘}) ) pwd = fields.CharField( max_length=12, widget=widgets.PasswordInput(attrs={‘class‘:‘c1‘}) ) #f 验证 #生成HTML (保留上一次提交的数据) #新URL方式操作(Form方式) #Ajax请求 验证(*) + 生成HTML 验证(*)
10,from,choices
models.py from django.db import models # Create your models here. class UserInfo(models.Model): name = models.CharField(max_length=32) email = models.EmailField() def clean(self): from django.core.exceptions import ValidationError c = UserInfo.objects.filter(name=self.name).count() if c: raise ValidationError(message=‘用户名已经存在‘,code=‘li‘) class UserType(models.Model): name = models.CharField(max_length=32) def __str__(self): return self.name ########### from.py from django.forms import widgets from django import forms from django.forms import fields from app import models from django.forms.models import ModelChoiceField,ModelMultipleChoiceField class UserInfoForm(forms.Form): user = fields.CharField( required=False, widget=widgets.Textarea(attrs={‘class‘:‘c1‘}) ) pwd = fields.CharField( max_length=12, widget=widgets.PasswordInput(attrs={‘class‘:‘c1‘}) ) user_type = fields.ChoiceField( choices = [], widget=widgets.Select ) user_type2 = fields.ChoiceField(widget=widgets.Select(choices=[])) #django自带 #ModelMultipleChoiceField多选 user_type3 = ModelChoiceField( empty_label=‘请选择类型‘, queryset=models.UserType.objects.all(), to_field_name=‘id‘ ) def __init__(self,*args,**kwargs): super(UserInfoForm,self).__init__(*args,**kwargs) self.fields[‘user_type‘].choices = models.UserType.objects.values_list(‘id‘,‘name‘) self.fields[‘user_type2‘].widget.choices = models.UserType.objects.values_list(‘id‘,‘name‘) ######### index.html <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <p>{{ obj.user }}</p> <p>{{ obj.pwd }}</p> <p>{{ obj.user_type }}</p> <p>{{ obj.user_type2 }}</p> <p>{{ obj.user_type3 }}</p> </body> </html>
11,Form类
创建Form类时,主要涉及到 【字段】 和 【插件】,字段用于对用户请求数据的验证,插件用于自动生成HTML;
1、Django内置字段如下:
http://www.cnblogs.com/wupeiqi/articles/6144178.html
Field required=True, 是否允许为空 widget=None, HTML插件 label=None, 用于生成Label标签或显示内容 initial=None, 初始值 help_text=‘‘, 帮助信息(在标签旁边显示) error_messages=None, 错误信息 {‘required‘: ‘不能为空‘, ‘invalid‘: ‘格式错误‘} show_hidden_initial=False, 是否在当前插件后面再加一个隐藏的且具有默认值的插件(可用于检验两次输入是否一直) validators=[], 自定义验证规则 localize=False, 是否支持本地化 disabled=False, 是否可以编辑 label_suffix=None Label内容后缀 CharField(Field) max_length=None, 最大长度 min_length=None, 最小长度 strip=True 是否移除用户输入空白 IntegerField(Field) max_value=None, 最大值 min_value=None, 最小值 FloatField(IntegerField) ... DecimalField(IntegerField) max_value=None, 最大值 min_value=None, 最小值 max_digits=None, 总长度 decimal_places=None, 小数位长度 BaseTemporalField(Field) input_formats=None 时间格式化 DateField(BaseTemporalField) 格式:2015-09-01 TimeField(BaseTemporalField) 格式:11:12 DateTimeField(BaseTemporalField)格式:2015-09-01 11:12 DurationField(Field) 时间间隔:%d %H:%M:%S.%f ... RegexField(CharField) regex, 自定制正则表达式 max_length=None, 最大长度 min_length=None, 最小长度 error_message=None, 忽略,错误信息使用 error_messages={‘invalid‘: ‘...‘} EmailField(CharField) ... FileField(Field) allow_empty_file=False 是否允许空文件 ImageField(FileField) ... 注:需要PIL模块,pip3 install Pillow 以上两个字典使用时,需要注意两点: - form表单中 enctype="multipart/form-data" - view函数中 obj = MyForm(request.POST, request.FILES) URLField(Field) ... BooleanField(Field) ... NullBooleanField(BooleanField) ... ChoiceField(Field) ... choices=(), 选项,如:choices = ((0,‘上海‘),(1,‘北京‘),) required=True, 是否必填 widget=None, 插件,默认select插件 label=None, Label内容 initial=None, 初始值 help_text=‘‘, 帮助提示 ModelChoiceField(ChoiceField) ... django.forms.models.ModelChoiceField queryset, # 查询数据库中的数据 empty_label="---------", # 默认空显示内容 to_field_name=None, # HTML中value的值对应的字段 limit_choices_to=None # ModelForm中对queryset二次筛选 ModelMultipleChoiceField(ModelChoiceField) ... django.forms.models.ModelMultipleChoiceField TypedChoiceField(ChoiceField) coerce = lambda val: val 对选中的值进行一次转换 empty_value= ‘‘ 空值的默认值 MultipleChoiceField(ChoiceField) ... TypedMultipleChoiceField(MultipleChoiceField) coerce = lambda val: val 对选中的每一个值进行一次转换 empty_value= ‘‘ 空值的默认值 ComboField(Field) fields=() 使用多个验证,如下:即验证最大长度20,又验证邮箱格式 fields.ComboField(fields=[fields.CharField(max_length=20), fields.EmailField(),]) MultiValueField(Field) PS: 抽象类,子类中可以实现聚合多个字典去匹配一个值,要配合MultiWidget使用 SplitDateTimeField(MultiValueField) input_date_formats=None, 格式列表:[‘%Y--%m--%d‘, ‘%m%d/%Y‘, ‘%m/%d/%y‘] input_time_formats=None 格式列表:[‘%H:%M:%S‘, ‘%H:%M:%S.%f‘, ‘%H:%M‘] FilePathField(ChoiceField) 文件选项,目录下文件显示在页面中 path, 文件夹路径 match=None, 正则匹配 recursive=False, 递归下面的文件夹 allow_files=True, 允许文件 allow_folders=False, 允许文件夹 required=True, widget=None, label=None, initial=None, help_text=‘‘ GenericIPAddressField protocol=‘both‘, both,ipv4,ipv6支持的IP格式 unpack_ipv4=False 解析ipv4地址,如果是::ffff:192.0.2.1时候,可解析为192.0.2.1, PS:protocol必须为both才能启用 SlugField(CharField) 数字,字母,下划线,减号(连字符) ... UUIDField(CharField) uuid类型
12,From内置钩子验证
##### views.py from django.shortcuts import render from app.forms import RegisterForm # Create your views here. def index(request): if request.method == "GET": obj = RegisterForm() #传递默认值 #obj = RegisterForm({‘user‘:‘alex‘}) return render(request,‘index.html‘,{‘obj‘:obj}) elif request.method == "POST": obj = RegisterForm(request.POST,request.FILES) obj.is_valid() #### froms.py from django.core.exceptions import ValidationError class RegisterForm(forms.Form): user = fields.CharField() email = fields.EmailField def clean_user(self): c = models.UserInfo.objects.filter(name=self.cleaned_data[‘user‘]).count() if not c: return self.cleaned_data[‘user‘] else: raise ValidationError(‘用户名已经存在‘,code=‘xx‘) def clean_email(self): return self.cleaned_data[‘email‘] class LoginFrom(forms.Form): user = fields.CharField() pwd = fields.CharField() #自定义表达式 #pwd = fields.CharField(validators=[]) #验证用户是否存在 def clean_user(self): c = models.UserInfo.objects.filter(name=self.cleaned_data[‘user‘]).count() if not c: return self.cleaned_data[‘user‘] else: raise ValidationError(‘用户名已经存在‘, code=‘xx‘) #验证密码是否正确 def clean(self): c = models.UserInfo.objects.filter(name=self.cleaned_data[‘user‘],pwd=self.cleaned_data[‘password‘]).count() if c: return self.cleaned_data else: raise ValidationError(‘用户名或密码错误‘) #其他钩子 def _post_clean(self): pass
from验证
urls.py from django.contrib import admin from django.urls import path from django.conf.urls import url,include #from app import views from app.views import test from app.views import account urlpatterns = [ #path(‘admin/‘, admin.site.urls), url(r‘^index/‘,test.index), url(r‘^login.html$‘,account.login), ] #### index.py from django.shortcuts import render from app.forms import UserInfoForm # Create your views here. def index(request): if request.method == "GET": obj = UserInfoForm() #传递默认值 #obj = UserInfoForm({‘user‘:‘alex‘}) return render(request,‘index.html‘,{‘obj‘:obj}) elif request.method == "POST": obj = UserInfoForm(request.POST,request.FILES) obj.is_valid() #### login.html <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>login</title> </head> <body> <form id="fm"> {% csrf_token %} <p><input type="text" name="username" /></p> <p><input type="text" name="password" /></p> <a id="submit">提交</a> </form> <script src="/static/jquery-1.12.4.js"></script> <script> $(function(){ $(‘$submit‘).click(function(){ $.ajax({ url:‘/login.html‘, type: ‘POST‘, data: $(‘#fm‘).serialize(), success: function(arg){ arg = JSON.parse(arg); console.log(arg); }, error: function(){ } }) }) }) </script> </body> </html> #### account.py from django.forms import fields from django.forms import widgets from django import forms from django.shortcuts import render,HttpResponse class LoginFrom(forms.Form): username = fields.CharField() password = fields.CharField( max_length=64, min_length=12, ) ###自定义jsnon 默认json只支持python类型 from django.core.exceptions import ValidationError import json class JsonCustomEncoder(json.JSONEncoder): def default(self,field): if isinstance(field,ValidationError): return {‘code‘: field.code,‘messages‘:field.message} else: return json.JSONEncoder.default(self,field) def login(request): if request.method == ‘GET‘: return render(request,‘login.html‘) elif request.method == "POST": ret = {‘status‘:True,‘error‘:None,‘date‘:None} obj = LoginFrom(request.POST) if obj.is_valid(): print(obj.cleaned_data) else: ret[‘error‘] = obj.error.as_data() result = json.dumps(ret,cls=JsonCustomEncoder) return HttpResponse(result)
自定义json
第一种 from django.core import serializrs v = models.tb.objects.all() data = serializers.serialize("json",v) 第二种 import json from datetime import date from datetime import datetime class JsonCustomEncoder(json.JSONEncoder): def default(self,field): if isinstance(field,datetime): return field.atrftime(‘%Y-%m-%d %H:%M:%s‘) elif isinstance(field,date): return field.strftime(‘%Y-%m-%d‘) else: return json.JSONEncoder.default(self,field) v = models.tb.objects.values(‘id‘,‘name‘,‘ctime‘) v = list(v) v = json.dumps(v,cls=JsonCustomEncoder) ##################### v = models.UserType.objects.values(‘id‘,‘name‘) v = list(v) return HttpResponse(json.dumps(v))
登录验证吗
if request,method == POST: if request.session[‘CheckCode‘].upper() == request.POST.get(‘check_code‘).upper(): pass else: print(‘验证码错误‘) return render(request,‘login.html‘)
12,obj.is_valid()错误信息
from app01.forms import RegisterForm from django.core.excptions import NON_FIELD_ERRORS #NON_FIELD_ERRORS = __all__ obj = RegisterForm(request.POST) if obj.is_valid(): obj.cleand_data else: obj.errros { "__all__": [], ‘user‘:[{‘code‘:‘required‘,‘message‘:‘xxx‘}], ‘pwd‘:[{‘code‘:‘required‘,‘message‘:‘xxx‘}], }
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