在 Flask 中生成动态 URL

先决条件： Flask 基础知识

创建应用程序时，对每个 URL 进行硬编码非常麻烦。解决此问题的更好方法是构建动态 URL。让我们先简单了解几个常用术语的含义。

动态路由：获取URL中的动态数据（变量名），然后使用的过程。
变量规则：可以通过用标记部分来将可变部分添加到 URL。

让我们首先创建一个基本的烧瓶应用程序：

Python3

#importing the flask Module
from flask import Flask
  
# Flask constructor takes the name of
# current module (__name__) as argument
app = Flask(__name__)
  
@app.route('/')
# ‘/’ URL is bound with hello_world() function.
def home():
    return 'You are at home page.'
  
@app.route('/allow')
def allow():
    return 'You have been allowed to enter.'
  
@app.route('/disallow')
def disallow():
    return 'You have not been allowed to enter.'
  
# main driver function
if __name__ == '__main__':
    # run() method of Flask class runs the application
    # on the local development server.
    app.run()

Python3

#importing the flask Module
from flask import Flask
  
# Flask constructor takes the name of
# current module (__name__) as argument
app = Flask(__name__)
  
@app.route('/')
# ‘/’ URL is bound with hello_world() function.
def home():
    return 'You are at home page.'
  
# Use of  in the 
# route() decorator.
@app.route('/allow/')
def allow(Number):
    if Number < 25:
        return f'You have been allowed to enter beause your number is {str(Number)}'
    else:
       return f'You are not allowed'
  
# main driver function
if __name__ == '__main__':
    # run() method of Flask class runs the application
    # on the local development server.
    app.run()

输出：

现在考虑这样一种情况，您有很多用户，并且您希望将用户路由到在 URL 中包含他或她的姓名或 ID 以及模板的特定页面。如果您尝试手动执行此操作，则必须为每个用户手动键入完整的 URL。这样做可能非常乏味，几乎不可能。但是，这可以通过使用带有称为动态路由的东西的烧瓶来解决。

动态路由

我们现在将看看使用变量规则的更好方法。我们将为每个路由添加一个。或者，我们还可以使用每个变量名称定义转换器。默认情况下，转换器是String 。

例子：

@app.route('allow/')

OR

@app.route('allow/')

一些转换器是：

String	(default) accepts any text without a slash
int	accepts positive integers
float	accepts positive floating point values
path	like string but also accepts slashes
uuid	accepts UUID strings

让我们允许 ID 小于 25 的用户访问该页面。下面给出了带有动态 URL 绑定的修改后的代码。该函数使用在 route() 装饰器中传递的作为参数。

@app.route('/allow/')
def allow(Number):
    if Number < 25:
        return f'You have been allowed to enter beause\
         your number is {str(Number)}'
    else:
       return f'You are not allowed'

蟒蛇3

#importing the flask Module
from flask import Flask
  
# Flask constructor takes the name of
# current module (__name__) as argument
app = Flask(__name__)
  
@app.route('/')
# ‘/’ URL is bound with hello_world() function.
def home():
    return 'You are at home page.'
  
# Use of  in the 
# route() decorator.
@app.route('/allow/')
def allow(Number):
    if Number < 25:
        return f'You have been allowed to enter beause your number is {str(Number)}'
    else:
       return f'You are not allowed'
  
# main driver function
if __name__ == '__main__':
    # run() method of Flask class runs the application
    # on the local development server.
    app.run()

输出：