search
HomeBackend DevelopmentPython Tutorial深入讲解Python编程中的字符串

Python转义字符
在需要在字符中使用特殊字符时,python用反斜杠(\)转义字符。如下表:

Python字符串运算符
下表实例变量a值为字符串"Hello",b变量值为"Python":

Python字符串格式化
Python 支持格式化字符串的输出 。尽管这样可能会用到非常复杂的表达式,但最基本的用法是将一个值插入到一个有字符串格式符 %s 的字符串中。
在 Python 中,字符串格式化使用与 C 中 sprintf 函数一样的语法。
如下实例:

#!/usr/bin/python

print "My name is %s and weight is %d kg!" % ('Zara', 21) 

以上实例输出结果:

My name is Zara and weight is 21 kg!


python字符串格式化符号:

格式化操作符辅助指令:

Python三引号(triple quotes)
python中三引号可以将复杂的字符串进行复制:
python三引号允许一个字符串跨多行,字符串中可以包含换行符、制表符以及其他特殊字符。
三引号的语法是一对连续的单引号或者双引号(通常都是成对的用)。

 >>> hi = '''hi 
there'''
>>> hi  # repr()
'hi\nthere'
>>> print hi # str()
hi 
there 

三引号让程序员从引号和特殊字符串的泥潭里面解脱出来,自始至终保持一小块字符串的格式是所谓的WYSIWYG(所见即所得)格式的。
一个典型的用例是,当你需要一块HTML或者SQL时,这时用字符串组合,特殊字符串转义将会非常的繁琐。

 errHTML = '''
<HTML><HEAD><TITLE>
Friends CGI Demo</TITLE></HEAD>
<BODY><h3 id="ERROR">ERROR</h3>
<B>%s</B><P>
<FORM><INPUT TYPE=button VALUE=Back
ONCLICK="window.history.back()"></FORM>
</BODY></HTML>
'''
cursor.execute('''
CREATE TABLE users ( 
login VARCHAR(8), 
uid INTEGER,
prid INTEGER)
''')

Unicode 字符串
Python 中定义一个 Unicode 字符串和定义一个普通字符串一样简单:

>>> u'Hello World !'
u'Hello World !'


引号前小写的"u"表示这里创建的是一个 Unicode 字符串。如果你想加入一个特殊字符,可以使用 Python 的 Unicode-Escape 编码。如下例所示:

>>> u'Hello\u0020World !'
u'Hello World !'

被替换的 \u0020 标识表示在给定位置插入编码值为 0x0020 的 Unicode 字符(空格符)。

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
The Main Purpose of Python: Flexibility and Ease of UseThe Main Purpose of Python: Flexibility and Ease of UseApr 17, 2025 am 12:14 AM

Python's flexibility is reflected in multi-paradigm support and dynamic type systems, while ease of use comes from a simple syntax and rich standard library. 1. Flexibility: Supports object-oriented, functional and procedural programming, and dynamic type systems improve development efficiency. 2. Ease of use: The grammar is close to natural language, the standard library covers a wide range of functions, and simplifies the development process.

Python: The Power of Versatile ProgrammingPython: The Power of Versatile ProgrammingApr 17, 2025 am 12:09 AM

Python is highly favored for its simplicity and power, suitable for all needs from beginners to advanced developers. Its versatility is reflected in: 1) Easy to learn and use, simple syntax; 2) Rich libraries and frameworks, such as NumPy, Pandas, etc.; 3) Cross-platform support, which can be run on a variety of operating systems; 4) Suitable for scripting and automation tasks to improve work efficiency.

Learning Python in 2 Hours a Day: A Practical GuideLearning Python in 2 Hours a Day: A Practical GuideApr 17, 2025 am 12:05 AM

Yes, learn Python in two hours a day. 1. Develop a reasonable study plan, 2. Select the right learning resources, 3. Consolidate the knowledge learned through practice. These steps can help you master Python in a short time.

Python vs. C  : Pros and Cons for DevelopersPython vs. C : Pros and Cons for DevelopersApr 17, 2025 am 12:04 AM

Python is suitable for rapid development and data processing, while C is suitable for high performance and underlying control. 1) Python is easy to use, with concise syntax, and is suitable for data science and web development. 2) C has high performance and accurate control, and is often used in gaming and system programming.

Python: Time Commitment and Learning PacePython: Time Commitment and Learning PaceApr 17, 2025 am 12:03 AM

The time required to learn Python varies from person to person, mainly influenced by previous programming experience, learning motivation, learning resources and methods, and learning rhythm. Set realistic learning goals and learn best through practical projects.

Python: Automation, Scripting, and Task ManagementPython: Automation, Scripting, and Task ManagementApr 16, 2025 am 12:14 AM

Python excels in automation, scripting, and task management. 1) Automation: File backup is realized through standard libraries such as os and shutil. 2) Script writing: Use the psutil library to monitor system resources. 3) Task management: Use the schedule library to schedule tasks. Python's ease of use and rich library support makes it the preferred tool in these areas.

Python and Time: Making the Most of Your Study TimePython and Time: Making the Most of Your Study TimeApr 14, 2025 am 12:02 AM

To maximize the efficiency of learning Python in a limited time, you can use Python's datetime, time, and schedule modules. 1. The datetime module is used to record and plan learning time. 2. The time module helps to set study and rest time. 3. The schedule module automatically arranges weekly learning tasks.

Python: Games, GUIs, and MorePython: Games, GUIs, and MoreApr 13, 2025 am 12:14 AM

Python excels in gaming and GUI development. 1) Game development uses Pygame, providing drawing, audio and other functions, which are suitable for creating 2D games. 2) GUI development can choose Tkinter or PyQt. Tkinter is simple and easy to use, PyQt has rich functions and is suitable for professional development.

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

AI Hentai Generator

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)
1 months agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. Best Graphic Settings
1 months agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. How to Fix Audio if You Can't Hear Anyone
1 months agoBy尊渡假赌尊渡假赌尊渡假赌
R.E.P.O. Chat Commands and How to Use Them
1 months agoBy尊渡假赌尊渡假赌尊渡假赌

Hot Tools

mPDF

mPDF

mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

MantisBT

MantisBT

Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.

Safe Exam Browser

Safe Exam Browser

Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.

Dreamweaver Mac version

Dreamweaver Mac version

Visual web development tools

ZendStudio 13.5.1 Mac

ZendStudio 13.5.1 Mac

Powerful PHP integrated development environment