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超轻量级php框架startmvc

Django 路由层URLconf的实现

更新时间:2020-08-17 10:30:01 作者:startmvc
分组分组的目的:让服务端获得url中的具体数据,通过分组,把需要的数据按函数传参的方

分组

分组的目的:让服务端获得url中的具体数据,通过分组,把需要的数据按函数传参的方式传递给服务器后台

1-无名分组

若要从URL 中捕获一个值,只需要在它周围放置一对圆括号


# app01/urls.py
from django.urls import path, re_path
from app01 import views


app_name = "app01"
urlpatterns = [

 path("login/", views.login, name="Log"),
 re_path(r"articles/([0-9]{4})/([0-9]){2}/", views.articles),

]


# app01/views.py
def articles(request, year, month ):
 print(year, month)
 return HttpResponse(year+"-"+month)

2-有名分组

在更高级的用法中,可以使用命名的正则表达式组来捕获URL 中的值并以关键字 参数传递给视图。

在Python 正则表达式中,命名正则表达式组的语法是(?P<name>),其中name 是组的名称,下面是以上URLconf 使用命名组的重写。


# app01/urls.py
from django.urls import path, re_path
from app01 import views

app_name = "app01"
urlpatterns = [

 path("login/", views.login, name="Log"),
 re_path(r"articles/(?P<year>[0-9]{4})/(?P<month>[0-9]{2}/)", views.articles),
]

捕获的值作为关键字参数而不是位置参数传递给视图函数


# app01/views.py
def articles(request, month, year ):
 print(year, month)
 return HttpResponse(year+"-"+month)

分发

分发的目的:解决一个django项目中因为存在多个应用app导致project下面的urls臃肿和分配混乱的问题

分发的具体操作流程是:

step1:项目文件下的urls.py,使用include()


# project/urls.py
from django.contrib import admin
from django.urls import path, include

urlpatterns = [
 path('admin/', admin.site.urls),
 path(r"app01/", include("app01.urls")),
]

step2:app下的具体url


# app01/urls.py
from django.urls import path
from app01 import views

urlpatterns = [
 path("login/", views.login),

]

step3:视图函数render时模板路径前缀


# app01/views.py
from django.shortcuts import render
# Create your views here.

def login(request):

 return render(request, "app01/login.html")

step4:模板


# app01/templates/app01/login.html
<!DOCTYPE html>
<html lang="en">
<head>
 <meta charset="UTF-8">
 <title>app01_title</title>
</head>
<body>
 <h2>app01_login</h2>
 <hr>
 <form action="" method="post">
 <p>用户名 <input type="text" name="name"></p>
 <p>密码 <input type="password" name="pwd"></p>
 <p><input type="submit" value="登录"></p>
 </form>

</body>
</html>

反向解析

反向解析的目的:解决url硬编码的问题,即不能写死一个url,否则日后修改url,造成的维护成本巨大

此时可以给url命名,然后可以在视图和模板中使用url别名,反向解析出正式的url

反向解析分两种:模板中解析、视图中解析

模板中解析 <form action="{% url "Art" 12 %}" method="post">


# app01/urls.py
from django.urls import path
from app01 import views

urlpatterns = [

 path("login/", views.login, name="Log"),
 path("articles/<int:id>/", views.articles, name="Art"), #有参

]


# app01/templates/app01/login.html
<form action="{% url "Log" %}" method="post">
 <p>用户名 <input type="text" name="name"></p>
 <p>密码 <input type="password" name="pwd"></p>
 <p><input type="submit" value="登录"></p>
</form>

<form action="{% url "Art" 12 %}" method="post">
 <p>用户名 <input type="text" name="name"></p>
 <p>密码 <input type="password" name="pwd"></p>
 <p><input type="submit" value="登录"></p>
</form>

视图中解析 reverse("Art", args=(id,))


# app01/views.py
from django.shortcuts import render
from django.urls import reverse

# Create your views here.

def login(request):
 
 print(reverse('log'))
 id=10
 print(reverse("Art", args=(id,)))
 
 return render(request, "app01/login.html")

命名空间

命名空间要配合反向解析使用,当存在多个app,url的name冲突时,需要指定该name的命名空间


# project/urls.py
from django.contrib import admin
from django.urls import path, include

urlpatterns = [
 path('admin/', admin.site.urls),
 path(r"app01/", include("app01.urls", namespace="app01")),
 path(r"app02/", include("app02.urls", namespace="app02")),
]

在django2.x中,app01/url.py需要添加 app_name = "app01"


# app01/urls.py
from django.urls import path
from app01 import views

app_name = "app01"
urlpatterns = [
 path("login/", views.login, name="Log"),

]


# app01/views.py(需要时设置)
from django.shortcuts import render
from django.urls import reverse
# Create your views here.

def login(request):
 a = reverse("app01:Log")
 print("app01:", a)
 return render(request, "app01/login.html")


# app01/templates/app01/login.html(需要时设置)
<form action="{% url "app01:Log" %}" method="post">
 <p>用户名 <input type="text" name="name"></p>
 <p>密码 <input type="password" name="pwd"></p>
 <p><input type="submit" value="登录"></p>
 </form>

转换器

对于django2.0版本以后,出现新的path() urlconf,他有两个好处:

1:url修改维护变得简单

2:url获得的参数的数据类型不再是单纯的str,在path中可以通过转换器实现参数数据类型的转换

path()中存在5个内置转化器:

=1. str,匹配除了路径分隔符(/)之外的非空字符串,这是默认的形式 2. int,匹配正整数,包含0。 3. slug,匹配字母、数字以及横杠、下划线组成的字符串。 4. uuid,匹配格式化的uuid,如 075194d3-6885-417e-a8a8-6c931e272f00。 5. path,匹配任何非空字符串,包含了路径分隔符

使用方法:

step1: app01/urls.py


from django.urls import path, re_path
from app01 import views

app_name = "app01"
urlpatterns = [
 path("login/", views.login, name="Log"),
 # re_path(r"articles/(?P<year>[0-9]{4})/", views.articles),

 path("articles/<int:year>/<int:month>/", views.articles),
]

step2: app01/views.py


def articles(request, year, month):

 print(year, month)
 print(type(year))

 return HttpResponse("ok")

  • <int: year> 相当于re_path()中的 (?P[0-9]{4})
  • <> 表示有名分组,year是组名;int表示传参的数据类型是正整数(但包括0)

自定义转换器

step1: app01/my_converters.py


class YearConverter: 
 
 regex = '[0-9]{4}' 
 
 def to_python(self, value): 
 return int(value) 
 
 def to_url(self, value): 
 return '%04d' % value

step2: app01/urls.py


from django.urls import path, re_path, register_converter
from app01 import views, my_converters

register_converter(my_converters.YearConverter, 'year')
app_name = "app01"
urlpatterns = [

 path("login/", views.login, name="Log"),
 # re_path(r"articles/(?P<year>[0-9]{4})/", views.articles),
 # path("articles/<int:year>/<int:month>/", views.articles),
 
 path("books/<year:y>", views.books),
]

step3: app01/views.py


def books(request, y):

 print(y, type(y))
 return HttpResponse("ok,books")

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。

Django 路由层 URLconf Django 路由层 Django URLconf