查看此代码：def my_decorator(func):

return lambda: print("goodbye")

def greet():

print('hello')

result = my_decorator(greet)

result()

output:

goodbye

以下是完成相同任务的捷径：

^{pr2}$

@my_decorator语法接受其下面的函数greet，并进行以下调用：greet = my_decorator(greet)

必须定义my_decorator()函数，以便：它以函数作为参数。

返回函数。A Python decorator is a specific change to the Python syntax that

allows us to more conveniently alter functions and methods (and

possibly classes in a future version).

好的，假设您希望将添加到greet()函数所做的任何操作中：def my_decorator(func): # func = greet

def add_to_greet():

func() #

print('world') #

return add_to_greet

@my_decorator

def greet():

print('hello')

greet()

output:

hello

worldWhat does this line do @bottle.route('/static/')

好了，准备好了吗？如果@some_name语法指定了一个参数，例如：@wrapper('world')

def do_stuff():

首先python将执行以下调用：@wrapper('world')

def do_stuff():

...

#****HERE:

decorator = wrapper('world') #decorator is a newly created variable

必须将wrapper()函数定义为：以任何一个古老的论点为例，例如“世界”

返回一个函数：

将函数作为参数。在

返回函数。在

其次，python将执行调用：@wrapper('world')

def do_stuff():

...

decorator = wrapper('world')

#*****HERE:

do_stuff = decorator(do_stuff)

嘘！下面是一个例子：def wrapper(extra_greeting):

def my_decorator(func):

def add_to_greet():

func()

print(extra_greeting)

return add_to_greet

return my_decorator

@wrapper('world')

def greet():

print('hello')

greet()

output:

hello

world

现在，我们来分析一下这个装饰器：@bottle.route('/static/')

def server_static(filepath):bottle a module

route a function(or other callable) defined in the bottle module

'/static/' a route

瓶子模块可能是这样的：#bottle.py

def route(your_route): #your_route <= '/static/'

def my_decorator(func): #The decorator syntax will cause python to call this function with server_static as the argument

def do_stuff(filepath):

func(filepath) #Call the server_static() function with the part of the url that matched filepath

return do_stuff #This function will be called when your code calls server_static(...)

return my_decoratorIf its a fancy function call then why do it this way rather than just

calling the function?

先进的东西。在

注释：也许您忘了解释路由装饰器具体做了什么？@route('/hello')

def hello():

return "Hello World!"

The route() decorator binds a piece of code to an URL path. In this

case, we link the /hello path to the hello() function. This is called

a route (hence the decorator name) and is the most important concept

of this framework. You can define as many routes as you want. Whenever

a browser requests a URL, the associated function is called and the

return value is sent back to the browser. It’s as simple as that.

路径可以包含通配符：The simplest form of a wildcard consists of a name enclosed in angle

brackets (e.g. )....Each wildcard matches one or more

characters, but stops at the first slash (/).

The rule // matches as follows:Path Result

/save/123 {'action': 'save', 'item': '123'}

/save/123/ No Match

/save/ No Match

//123 No MatchFilters are used to define more specific wildcards, and/or transform

the matched part of the URL before it is passed to the callback. A

filtered wildcard is declared as The following standard filters are implemented:

:path matches all characters including the slash character in a non-greedy way and may be used to match more than one path

segment.