Flask +jinja2+bootstrap+sqlite3+sqlalchemy构建web基础学习总结

1. source codes
2. 样例演示, 有一天会失效

1 route 路由

1. 语法

   
   # 普通路由
   
   @app.route('/')
   def index():
       return 'Hello World!!!'
   
   
   
   # 路由传参
   
   @app.route('/users/<name>')
   def user(name):
       return 'user: ' + name
   
   
   
   # 指定参数类型， 参考下面2
   
   @app.route('/articles/<string:article_name>')
   def article(article_name):
       return 'article: ' + article_name
   
   
   
   # 指定 HTTP Methods  参考下面3
   
   @app.route('/login', methods=['GET', 'POST'])
   def login():
       if request.method == 'POST':
           do_the_login()
       else:
           show_the_login_form()
   
   
   # 获取表单数据
   
   @app.route('/search', methods=['POST'])
   def search():
       return 'key word: ' + request.form.get('search_key') + '<br> Find nothing.'

2. The following converters exist:

   string	accepts any text without a slash (the default)
   int	accepts integers
   float	like int but for floating point values
   path	like the default but also accepts slashes
   any	matches one of the items provided
   uuid	accepts UUID strings

3. Http Methods

   GET

   The browser tells the server to just get the information stored on that page and send it. This is probably the most common method.

   HEAD

   The browser tells the server to get the information, but it is only interested in the headers, not the content of the page. An application is supposed to handle that as if a GET request was received but to not deliver the actual content. In Flask you don’t have to deal with that at all, the underlying Werkzeug library handles that for you.

   POST

   The browser tells the server that it wants to post some new information to that URL and that the server must ensure the data is stored and only stored once. This is how HTML forms usually transmit data to the server.

   PUT

   Similar to POST but the server might trigger the store procedure multiple times by overwriting the old values more than once. Now you might be asking why this is useful, but there are some good reasons to do it this way. Consider that the connection is lost during transmission: in this situation a system between the browser and the server might receive the request safely a second time without breaking things. With POST that would not be possible because it must only be triggered once.

   DELETE

   Remove the information at the given location.

   OPTIONS

   Provides a quick way for a client to figure out which methods are supported by this URL. Starting with Flask 0.6, this is implemented for