Django (a)

Tag: cal time localhost new input set DEX OCA app

Learned a few days of Django. According to the official tutorial learned 4 knots. Probably has a general understanding of Django.

There are differences between apps and project.

What's the difference between a project and an app? An app was a WEB application that does something–e.g., a Weblog system, a database of public records or a simple poll app . A project is a collection of the configuration and apps for a particular website. A project can contain multiple apps. An app can is in multiple projects.

Application refers to the application of a website. Project, however, refers to the collection of applications. It manages the operation of the entire website.

Then I built a project called MySite, according to the tutorial built a application called polls. is a simple voting system.

The default app also has apps such as user management.

The system configuration is in the setting of the MySite directory.

such as database configuration, middleware, templates and so on. and your new app.

Installed_app = [

' Polls.apps.PollsConfig ',
' Django.contrib.admin ',
' Django.contrib.auth ',
' Django.contrib.contenttypes ',
' Django.contrib.sessions ',
' Django.contrib.messages ',
' Django.contrib.staticfiles ',

]

Some apps here are turned on by default. Like admin.

Then look at the new polls application.

Polls/    __init__.  PY    admin.  Apps.  Migrations__init__.  Models.  Tests.  Views.  PY                 

I'm talking about some of the files I used in my practice.

models.py

This is the file that created the database object.

Write the database model you need in this file.

Question(models.  Modelmodels.  Charfield(max_length=models.  Datetimefield(' date published ')          

The primary key is created by itself as a self-increment int.

Specific example:

Even the table names are generated for you.

How do I generate database data?

The command here is migrate.

What kind of data model is generated,

Look in this file.

polls/migrations/0001_initial.py:

You can see this before you execute the command.

Python manage.py sqlmigrate polls 0001

Final Execution command

Python manage.py Migrate

How does the program know polls this application?

In the polls directory under the apps.py to configure.

Migrate this command before it seems to have seen in Ror ...

It seems that these frameworks are actually similar.

And then the view.

The view is written mainly in the views.py file under Application.

What if I use HTML?

Create a template/polls/xxx.html under polls

The program will follow this path to find.

Then enter localhost:8000/polls/in the browser.

How does the backstage know which function in views.py is requested?

In the urls.py.

The URL () function is enough.

[    URL(R ' ^$ 'views.  IndexName=' index '),]          

url(regex, view, kwargs=none, name=none)

The URL () function passes four parameters, the first being a regular expression, which is the URL request path.

Then the view, referencing the functions in views.py.

The latter two parameters are optional.

Kwargs is a supplement to the URL. As follows:

URL(R ' ^blog/(? P<year>[0-9]{4})/$ 'views.  Year_archive{' foo 'Bar '}),          

The requested URL is/blog/2005/, and the function calling views.py isviews.year_archive(request, year=‘2005‘,foo=‘bar‘)

The last name can be used to define the name of the template.

Probably learned so much, and many of them are not very clear. We need to keep looking.

Django (a)