Shulou(Shulou.com)06/03 Report--

This article mainly shows you "how to use click in python", the content is easy to understand, clear, hope to help you solve your doubts, the following let the editor lead you to study and learn "how to use click in python" this article.

1. How to install

Use the command pip install click or install in PyCharm

two。 Isolated environment vitualenv

On linux or MAC

Sudo pip install virtualenv

Windows

Pip install virtualenv

43 how to activate

Now, whenever you want to work on a project, you just need to activate the appropriate environment. On OS X and Linux, do the following:

$. Venv/bin/activate

If you are a Windows user, the following command applies to you:

$venv\ scripts\ activate

Exit activation

$deactivate

Enter the following command to activate Click in virtualenv:

$pip install Click

4.click syntax

The function is decorated to become the Click command line tool click.command (). The easiest way is to decorate a function with this decorator to make it a callable script:

Import click

@ click.command ()

@ click.option ('--count', default=1, help='Number of greetings.')

@ click.option ('--name', prompt='Your name'

Help='The person to greet.')

Def hello (count, name):

"Simple program that greets NAME for a total of COUNT times."

For x in range (count):

Click.echo ('Hello% slots'% name)

If _ _ name__ = ='_ _ main__':

Hello ()

Execute according to the parameter format

$python hello.py-count=3

Your name: John

Hello John!

Hello John!

Hello John!

Automatically generate help documentation

$python hello.py-help

Usage: hello.py [OPTIONS]

Simple program that greets NAME for a total of COUNT times.

Options:

-- count INTEGER Number of greetings.

-- name TEXT The person to greet.

-- help Show this message and exit.

6. Print function click.echo

Use echo () instead of the regular print () function? The answer to this question is that Click tries to support Python 2 and Python 3 in the same way.

Since Click 2.0, the echo function also has good support for ANSI colors.

7. Nested command

Use @ click.group () to achieve the nesting of commands, that is, subcommands can exist

@ click.group ()

Def cli ():

Pass

@ click.command ()

Def initdb ():

Click.echo ('Initialized the database')

@ click.command ()

Def dropdb ():

Click.echo ('Dropped the database')

Cli.add_command (initdb)

Cli.add_command (dropdb)

As you can see, the group () decorator works like the command () decorator, but creates a Group object that provides multiple subcommands Group.add_command () that can be appended to it.

For simple scripts, you can also use the Group.command () decorator to automatically attach and create commands. The above script can be written as follows:

@ click.group ()

Def cli ():

Pass

@ cli.command ()

Def initdb ():

Click.echo ('Initialized the database')

@ cli.command ()

Def dropdb (): how much is the flow of people in Wuxi http://www.bhnnk120.com/

Click.echo ('Dropped the database')

You then call Group in the setuptools entry point or other calls:

If _ _ name__ = ='_ _ main__':

Cli ()

8. Add parameters

Add parameter @ click.option to add a parameter, use the option () and argument () decorators:

@ click.command ()

@ click.option ('--count', default=1, help='number of greetings')

@ click.argument ('name')

Def hello (count, name):

For x in range (count):

Click.echo ('Hello% slots'% name)

The generated help documents are as follows

$python hello.py-help

Usage: hello.py [OPTIONS] NAME

Options:

-- count INTEGER number of greetings

-- help Show this message and exit.

The generated help documents are as follows

$python hello.py-help

Usage: hello.py [OPTIONS] NAME

Options:

-- count INTEGER number of greetings

-- help Show this message and exit.

The above is all the content of the article "how to use click in python". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.