1. View functions:
Request Object------------- request:
1,HttpRequest.body:) Request original data
2,HttpRequest.path:) A string representing the requested path component (without domain name)
3,HttpRequest.method
4,HttpRequest.GET
5,HttpRequest.POST
6,HttpRequest.FILES
7,HttpResquest.user:) An AUTH_USER_Objects of type MODEL
- Response object:
return. HttpResponse(")] Returns an instance of a string
return render(request,"template", {":"}) return string instance
return Redirect ("/index/") Redirect
2. Template Language
First write the function in the views view function and return a rendering page:
views:
def foo (request):
name="li"
l=[111,2222,3333]
d={"info":[obj1,obj2...]}
return render(request,"index.html",locals())
Variable: {{name}}
------- Deep query period character. For example: {{d.info.0.name}
------- Filter {{name|date:'Y-m-d'}}
2. Tags:
for loop
{%for i in l%}
{{i}}
{%empty%}
<p>There are no qualifications </p>
{%endfor%}
if statement
{%if name="li"%}
<p> Yes</p>
{%elif%}
{%endif....%}
3. Template Syntax
(1) In masterBase.html: {%block con%}{%endblock%}
(2) Inherit the masterIndex.html:
{%extends"Base.html"%}" Inheritance
{%block con%}
{%endblock%}
3. models Model of ORM
1. Mapping relationship:
Table Name in sql----------Class Name of Python
Fields in sql--------Class properties of Python
Records in sql------Class objects for Python
2. Form operation
class Article(models.Model):
nid = models.BigAutoField(primary_key=True)
title = models.CharField(max_length=50, verbose_name='Article Title')
read_count = models.IntegerField(default=0)
(1) Add operation
views:
#Method 1:
article_obj=models.Article.objects.create(nid=1,title="yuan",read_count=12) # create Method returns the currently created article object
#Method 2:
article_obj=models.Article(nid=1,title="yuan",read_count=12)
article_obj.save()
//Delete:
models.Article.objects.filter(title="python").delete() # Default Cascade Delete
//Modify:
models.Article.objects.filter(title="python").update(read_count=F("read_count")+10)
//Query API:
<1> all(): Query all results #QuerySet
<2> filter(**kwargs): It contains objects that match the given filter criteria #QuerySet
<3> get(**kwargs): Returns the object that matches the filter criteria given. There is one and only one result.
//An error is thrown if more than one or none of the objects meet the filter criteria.# model object
<5> exclude(**kwargs): It contains objects that do not match the given filter criteria #QuerySet
<4> values(*field): Return a ValueQuerySet-A special QuerySet，What you get after running is not a series
model Instantiate an object, but an iterative sequence of dictionaries #QuerySet
<9> values_list(*field): It is associated with values()Very similar, it returns a tuple sequence. values A dictionary sequence is returned #QuerySet
<6> order_by(*field): Sort query results #QuerySet
<7> reverse(): Reverse sort of query results #QuerySet
<8> distinct(): Remove duplicate records from returned results #QuerySet
<10> count(): Return matching queries in database(QuerySet)Number of objects. # int
<11> first(): Return the first record # model object
<12> last(): Return to the last record # model object
<13> exists(): If QuerySet Contains data, returns True，Otherwise return False
querySet Support chain operation:
models.Article.objects.all().filter().values().distinct().count()
QuerySet Data type:
1,Sliceable, iterative [obj,....]
2,Lazy queries:
articles_list=models.Article.objects.all()
//Using articles_list, such as if articles_list, convert the sql statement at this time
3,Caching mechanism
articles_list=models.Article.objects.all()
for i in articles_list:
print(i.title) # hit the database
for i in articles_list:
print(i.title) # not hit the database
==============================================
for i in models.Article.objects.all():
print(i.title) # hit the database
for i in models.Article.objects.all():
print(i.title) # hit the database
4,Optimize Query
articles_list=models.Article.objects.all().iterator()
for i in articles_list:
print(i.title) # hit the database
for i in articles_list:
print(i.title) # No result
//Join Table Operation:
//Table relations:
class UserInfo(AbstractUser): # settings: AUTH_USER_MODEL = "blog.UserInfo"
"""
//User Information
"""
nid = models.BigAutoField(primary_key=True)
nickname = models.CharField(verbose_name='Nickname?', max_length=32,null=True)
telephone = models.CharField(max_length=11, blank=True, null=True, unique=True, verbose_name='Phone number')
avatar = models.FileField(verbose_name='Head portrait', upload_to='avatar', default="avatar/default.png")
create_time = models.DateTimeField(verbose_name='Creation Time', auto_now_add=True)
class Blog(models.Model):
"""
//Site Information
"""
nid = models.BigAutoField(primary_key=True)
title = models.CharField(verbose_name='Personal Blog Title', max_length=64)
site = models.CharField(verbose_name='Personal Blog Suffix', max_length=32, unique=True)
theme = models.CharField(verbose_name='Blog Theme', max_length=32)
user = models.OneToOneField(to='UserInfo', to_field='nid')
class Category(models.Model):
nid = models.AutoField(primary_key=True)
title = models.CharField(verbose_name='Category Title', max_length=32)
blog = models.ForeignKey(verbose_name='Owning Blog', to='Blog', to_field='nid')
class Article(models.Model):
nid = models.BigAutoField(primary_key=True)
title = models.CharField(max_length=50, verbose_name='Article Title')
desc = models.CharField(max_length=255, verbose_name='Article Description')
# category Field: and Article Object-Associated category object
category = models.ForeignKey(verbose_name='Article Type', to='Category', to_field='nid', null=True)
# user Field: and Article Object-Associated user field
user = models.ForeignKey(verbose_name='Owned User', to='UserInfo', to_field='nid')
tags = models.ManyToManyField(
to="Tag",
through='Article2Tag',
through_fields=('article', 'tag'),
)
class ArticleDetail(models.Model):
nid = models.AutoField(primary_key=True)
content = models.TextField(verbose_name='Article Content', )
article = models.OneToOneField(verbose_name='Owned Articles', to='Article', to_field='nid')
class Article2Tag(models.Model):
nid = models.AutoField(primary_key=True)
article = models.ForeignKey(verbose_name='Article', to="Article", to_field='nid')
tag = models.ForeignKey(verbose_name='Label', to="Tag", to_field='nid')
class Tag(models.Model):
nid = models.AutoField(primary_key=True)
title = models.CharField(verbose_name='Label Name', max_length=32)
blog = models.ForeignKey(verbose_name='Owning Blog', to='Blog', to_field='nid'
//Add record operation to associated table:
1,Create an article for:
user_obj=models.UserInfo.objects.get(nid=1)
category_obj=models.Category.objects.get(nid=2)
#################One-to-many relationship binding#########################
# Mode 1:
article_obj=models.Article.objects.create(nid=5,title="Pick up flowers at night"....,user=user_obj,category=category_obj)
# Mode 2:
article_obj=models.Article.objects.create(nid=5,title="Pick up flowers at night"....,user_id=1,category_id=2)
'''
Article:
nid title user_id category_id
5 Pick up flowers at night 1 2
'''