How is the framework different from the Library???

# Web Site Writing Basics # Pythonprogramming # frameworks # Library

The difference between a Library (library) and a Framework is one of the most confusing programs, because they are both "ready-made code that others have written for us," but the most important difference is "Inversion of Control." To see the most obvious difference, let's see the main difference: 1. The Analogy Library is like a "toolbox" or "furniture": you build your own house (write down the main structure), and you walk to pick up a net, pliers, or buy a finished sofa in your house. You control when you use it and where you put it. The framework is like a "prefabricated house" or a "flange structure": he makes the frame of the house, breaks through the portholes, sets the water pipe system up. You have to just decorate, paint, or add in the box he has left. You can't move the main pillar of the house as you like because it's attached to a large structure. 2. Who calls? (Inversion of Control) This is the technical intersection that clearly separates these two things. Library (We run the code): Our main code controls the game. Whenever you want a special function, call the Library to work. When you finish, the power comes back to our code. Framework: The Framework controls the game. It has its own structure and lifecycle. It tells us, "If you want the web to display a new page, put the code in this file," and the Framework will pick up our code to run it itself. 3. The table summarizes the differences of the Library (Library) Framework (Framework) Control (Control) We control: Choose when to use it. The Framework controls: Forcing us to write according to its rules and structure. The size and scope are usually small. The focus solves specific problems (such as compute, graph), large, covers the entire architecture of the system. The freedom to write code is very high. The file or write any style is low. The file must be placed and named as specified. Otherwise, the system will crash samples in PythonNumPy, Pandas, Requests, mathDjango, Flask, FastAPI4. Based on the example of real code using the Library (such as requests to retrieve web data), you can see that we are writing the first line of code continuously. When you want web data, you can call requests. Get (). One command ends Python # Our code is big.

Print ("Start working")

Import request

Response = request.get ("https://api.github.com") # Run the library at will.

Print (respond.status _ code)

Print ("End of work")

Using the Framework (such as Flask to create a website), you do not order the program to start from top to bottom normally, but you must create a function based on the Framework rules and leave the Framework as the manager to open the Server and run our function when someone accesses Pythonfrom flask import Flask.

app = Flask (_ _ name _ _)

# We must write the code under the Route that the Framework defines

@ app.route ("/")

DEF home ():

"Hello, this is the front page."

♪ The Framework will run the whole system itself

if _ _ name _ _ = = "_ _ main _ _":

app.run ()

Brief summary: If you need a tool to do some work from time to time = use the Library, but if you need a finished structure to build a large system and follow its rules = use the Framework, sir.