現(xiàn)在,我們有一個(gè)工作視圖在前面的章節(jié)中解釋。我們希望通過一個(gè)URL來訪問該視圖。 Django有他自己 URL映射的方式,現(xiàn)在我們來編輯項(xiàng)目中的 url.py 文件(myproject/url.py)完成。url.py 文件內(nèi)容看起來如下:
# Filename : example.py # Copyright : 2020 By Nhooo # Author by : www.soo66.com # Date : 2020-08-08 from django.conf.urls import patterns, include, url from django.contrib import admin admin.autodiscover() urlpatterns = patterns('', #Examples #url(r'^, 'myproject.view.home', name = 'home'), #url(r'^blog/', include('blog.urls')), url(r'^admin', include(admin.site.urls)), ) , 'myproject.view.home', name = 'home'), #url(r'^blog/', include('blog.urls')), url(r'^admin', include(admin.site.urls)), )
當(dāng)用戶在您的網(wǎng)絡(luò)應(yīng)用程序發(fā)起一個(gè)網(wǎng)頁的請(qǐng)求,Django控制器會(huì)接管通過url.py文件來尋找相應(yīng)的視圖,然后返回HTML響應(yīng)或如果沒有找到則返回404未找到錯(cuò)誤。最重要的是“urlpatterns” 元組。這就是定義URL和視圖之間的映射。一個(gè)映射的URL模式就像一個(gè)元組 ?
# Filename : example.py # Copyright : 2020 By Nhooo # Author by : www.soo66.com # Date : 2020-08-08 from django.conf.urls import patterns, include, url from django.contrib import admin admin.autodiscover() urlpatterns = patterns('', #Examples #url(r'^, 'myproject.view.home', name = 'home'), #url(r'^blog/', include('blog.urls')), url(r'^admin', include(admin.site.urls)), url(r'^hello/', 'myapp.views.hello', name = 'hello'), ) , 'myproject.view.home', name = 'home'), #url(r'^blog/', include('blog.urls')), url(r'^admin', include(admin.site.urls)), url(r'^hello/', 'myapp.views.hello', name = 'hello'), )
標(biāo)記行映射URL "/home" 到 myapp/ view.py文件中創(chuàng)建的Hello視圖。正如你看到上面的映射是由三個(gè)要素 -
模式? 一個(gè)正則表達(dá)式匹配以URL予以解決和映射。 能夠與python “re”模塊工作一切都符合的模式(非常有用在你想通過URL來傳遞參數(shù)時(shí))。 python到視圖的路徑?在你導(dǎo)入模塊時(shí)相同。 名稱?為了執(zhí)行URL反轉(zhuǎn),需要使用URL模式的命名來執(zhí)行上面示例。這樣做以后,啟動(dòng)服務(wù)器,通過以下URL訪問您的視圖:http://127.0.0.1/hello
到目前為止,我們已經(jīng)創(chuàng)建了“myprojects/url.py”文件的URL,然而,正如前面關(guān)于Django說明,創(chuàng)建一個(gè)應(yīng)用程序,最好是能夠重復(fù)使用在不同的項(xiàng)目中應(yīng)用。 這樣就可以很容易地看到的問題是什么,如果要保存所有網(wǎng)址中在“projecturl.py”文件中。 所以,最好的做法是創(chuàng)建每個(gè)應(yīng)用程序的“url.py”,并把它列入我們的主項(xiàng)目 url.py 文件(包括在我們的管理界面管理的 URL 之前)。
我們需要使用下面的代碼來創(chuàng)建一個(gè) urls.py 文件在 myapp 文件夾中(myapp/urls.py) ?
# Filename : example.py # Copyright : 2020 By Nhooo # Author by : www.soo66.com # Date : 2020-08-08 from django.conf.urls import patterns, include, url urlpatterns = patterns('', url(r'^hello/', 'myapp.views.hello', name = 'hello'),)
myproject/urls.py 將變更為以下-
# Filename : example.py # Copyright : 2020 By Nhooo # Author by : www.soo66.com # Date : 2020-08-08 from django.conf.urls import patterns, include, url from django.contrib import admin admin.autodiscover() urlpatterns = patterns('', #Examples #url(r'^, 'myproject.view.home', name = 'home'), #url(r'^blog/', include('blog.urls')), url(r'^admin', include(admin.site.urls)), url(r'^myapp/', include(myapp.urls)), ) , 'myproject.view.home', name = 'home'), #url(r'^blog/', include('blog.urls')), url(r'^admin', include(admin.site.urls)), url(r'^myapp/', include(myapp.urls)), )
我們已經(jīng)包括了 myapp 應(yīng)用程序的所有URL。這是通過訪問 home.html 為 “/hello”,現(xiàn)在是 “/myapp/hello” ,這是 Web應(yīng)用程序的更好和更容易理解的結(jié)構(gòu)。
再創(chuàng)建一個(gè)視圖文件:C:\myproject\templates\myapp\hello.html,其內(nèi)容如下:
# Filename : example.py # Copyright : 2020 By Nhooo # Author by : www.soo66.com # Date : 2020-08-08 <html> <head> <meta http-equiv="content-type" content="text/html; charset=utf-8"> <title>Hello </title> <meta name="robots" content="NONE,NOARCHIVE"> </style> </head> <body> <h2>Welcome to Nhooo .</h2> <p>This is my first Django App</p> <body> </html>
現(xiàn)在讓我們想象一下在 myapp 的 “morning” 的另一個(gè)視圖,我們希望它在映射myapp/url.py,we will then change our myapp/url.py to ?
# Filename : example.py # Copyright : 2020 By Nhooo # Author by : www.soo66.com # Date : 2020-08-08 from django.conf.urls import patterns, include, url urlpatterns = patterns('', url(r'^hello/', 'myapp.views.hello', name = 'hello'), url(r'^morning/', 'myapp.views.morning', name = 'morning'), )
這可以被重構(gòu)為 ?
# Filename : example.py # Copyright : 2020 By Nhooo # Author by : www.soo66.com # Date : 2020-08-08 from django.conf.urls import patterns, include, url urlpatterns = patterns('myapp.views', url(r'^hello/', 'hello', name = 'hello'), url(r'^morning/', 'morning', name = 'morning'),)
正如你所看到的,我們現(xiàn)在使用 urlpatterns 元組的第一個(gè)元素。當(dāng)你想改變應(yīng)用程序的名稱時(shí),這非常有用。
現(xiàn)在我們知道如何映射URL,如何組織他們,現(xiàn)在就讓我們來看看如何將參數(shù)傳遞給視圖。一個(gè)經(jīng)典的文章實(shí)例(您要訪問文章到“/articles/article_id”)。
傳遞參數(shù)是通過URL模式正則表達(dá)式捕捉它們完成的。如果我們有類似以下的視圖 “myapp/view.py”
# Filename : example.py # Copyright : 2020 By Nhooo # Author by : www.soo66.com # Date : 2020-08-08 from django.shortcuts import render from django.http import HttpResponse def hello(request): return render(request, "hello.html", {}) def viewArticle(request, articleId): text = "Displaying article Number : %s"%articleId return HttpResponse(text)
我們想把它映射放在myapp/urls.py ,所以我們可以通過 “/myapp/article/articleId” 訪問, 我們需要在下列 “myapp/urls.py” 定義?
# Filename : example.py # Copyright : 2020 By Nhooo # Author by : www.soo66.com # Date : 2020-08-08 from django.conf.urls import url from . import views urlpatterns = [ url(r'^hello', views.hello, name='hello'), url(r'^article/(\d+)/', views.viewArticle, name = 'article'), url(r'^, views.index, name='index'), ] , views.index, name='index'), ]
當(dāng)Django會(huì)看到URL: “/myapp/article/42” ,它將傳遞參數(shù)'42'到viewArticle視圖,在瀏覽器中,應(yīng)該得到以下結(jié)果 -
注意,參數(shù)的順序這里是很重要的。假設(shè)我們希望查看一年中某個(gè)一個(gè)月的文章列表,現(xiàn)在添加一個(gè) viewArticles 視圖。 view.py 代碼變?yōu)?nbsp;-
# Filename : example.py # Copyright : 2020 By Nhooo # Author by : www.soo66.com # Date : 2020-08-08 from django.shortcuts import render from django.http import HttpResponse def hello(request): return render(request, "hello.html", {}) def viewArticle(request, articleId): text = "Displaying article Number : %s"%articleId return HttpResponse(text) def viewArticles(request, month, year): text = "Displaying articles of : %s/%s"%(year, month) return HttpResponse(text)
相應(yīng)的 myapp/urls.py 文件看起來如下 ?
# Filename : example.py # Copyright : 2020 By Nhooo # Author by : www.soo66.com # Date : 2020-08-08 from django.conf.urls import patterns, include, url urlpatterns = patterns('myapp.views', url(r'^hello/', 'hello', name = 'hello'), url(r'^morning/', 'morning', name = 'morning'), url(r'^article/(\d+)/', 'viewArticle', name = 'article'), url(r'^articles/(\d{2})/(\d{4})', 'viewArticles', name = 'articles'),)
現(xiàn)在,當(dāng)您訪問 http://localhost:8000/myapp/articles/12/2015/,會(huì)得到'Displaying articles of: 2015/12' ,但如果轉(zhuǎn)換參數(shù),將不能得到相同的結(jié)果。
為避免這種情況,有可能一個(gè)URL參數(shù)會(huì)鏈接到視圖參數(shù)。因此 url.py 將成為 -
# Filename : example.py # Copyright : 2020 By Nhooo # Author by : www.soo66.com # Date : 2020-08-08 from django.conf.urls import patterns, include, url urlpatterns = patterns('myapp.views', url(r'^hello/', 'hello', name = 'hello'), url(r'^morning/', 'morning', name = 'morning'), url(r'^article/(\d+)/', 'viewArticle', name = 'article'), url(r'^articles/(?P\d{2})/(?P\d{4})', 'viewArticles', name = 'articles'),)