Home Backend Development Python Tutorial Introduction to Python file processing

Introduction to Python file processing

Mar 17, 2017 pm 03:37 PM
python

Related API:

Folder:

Get the current working directory, that is, the directory path where the current Python script works: os. getcwd()

Returns all file and directory names in the specified directory: os.listdir()

Function is used to delete a file: os.remove()

Delete multiple directories: os.removedirs(r "c:\python")

Check whether the given path is a file: os.path.isfile()

Check whether the given path is a directory: os.path.isdir()

Judge Whether it is an absolute path: os.path.isabs()

Check whether the given path actually exists: os.path.exists()

Return the directory name and file name of a path: os.path.split()

Separate extension: os.path.splitext()

Get path name: os.path.dirname()

Get file name: os.path.basename()

Run shell command: os.system()

Read and set environment variables: os. getenv() and os.putenv()

gives the line terminator used by the current platform: os.linesep Windows uses '\r\n', Linux uses '\n' and Mac uses '\r'

Indicate the platform you are using: os.name For Windows it is 'nt' and for Linux/Unix users it is 'posix'

Rename: os.rename ( old, new)

Create a multi-level directory: os.makedirs(r "c:\python\test")

Create a single directory: os.mkdir(" test”)

Get file attributes: os.stat(file)

Modify file permissions and timestamp: os.chmod(file)

Terminate the current process: os.exit()

Get the file size: os.path.getsize(filename)

File:

fp = open("test.txt",w) Open a file directly. If the file does not exist, create the file

About open mode:

w Open in writing mode,

a Open in append mode (start from EOF, create new file if necessary)

r+ Open in read-write mode

w+ Open in read-write mode (see w)

a+ Open in read-write mode (see a)

rb Open in binary read mode

wb Open in binary write mode (see w)

ab Open in binary append mode (see a)

rb+ Open in binary read-write mode (see r+)

wb+ Open in binary read-write mode (see w+)

ab+ Open in binary read-write mode (see a+)

fp.read([size])                                                                                                                                                                                                                                                                            #([size])               #Read a line, if size is defined, it is possible to return only a part of the line

fp.readlines([size])                                                                                                                                                                                                                                                Return this list. In fact, it is implemented internally by calling readline() in a loop. If the size parameter is provided, size represents the total length of the read content, which means that only a part of the file may be read.

FP.Write (STR)#Write STR into the file, WRITE () will not add a change of lines behind STR FP.Writelines (SEQ)# All contents are written to the file (multiple lines are written at once). This function also just writes faithfully, without adding anything after each line.

fp.close()                   #Close the file. Python will automatically close a file after it is no longer used. However, this function is not guaranteed. It is best to develop the habit of closing it yourself. If a file is operated on after it is closed, a ValueError will be generated.

fp.

flush

()

fp.fileno()                                                                                                                                                                           ‐   ‐ ‐ ‐ ‐                                                                          . )

fp.tell()                                                                                                                                                                                           ‐ ‐ ‐ ‐ ‐ ‐ ‐ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​, and move the file operation flag to the next One line. When a file is used in a statement such as

for

... in file, the next() function is called to implement traversal.

fp.seek(offset[,whence])             #Move the file operation mark to the offset position. This offset is generally calculated relative to the beginning of the file, and is generally a positive number. But this is not necessarily the case if the whence parameter is provided. whence can be 0 to start the calculation from the beginning, and 1 to use the current position as the origin. 2 means the calculation is performed with the end of the file as the origin. It should be noted that if the file is opened in a or a+ mode, the file operation mark will automatically return to the end of the file every time a write operation is performed. fp.truncate([size])                         #Cut the file to the specified size. The default is to cut to the position of the current file operation mark. If size is larger than the file size, depending on the system, the file may not be changed, the file may be padded to the corresponding size with 0, or some random content may be added.

The above is the detailed content of Introduction to Python file processing. For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website
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

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)
2 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Repo: How To Revive Teammates
4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌
Hello Kitty Island Adventure: How To Get Giant Seeds
4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Can the Python interpreter be deleted in Linux system? Can the Python interpreter be deleted in Linux system? Apr 02, 2025 am 07:00 AM

Regarding the problem of removing the Python interpreter that comes with Linux systems, many Linux distributions will preinstall the Python interpreter when installed, and it does not use the package manager...

How to solve the problem of Pylance type detection of custom decorators in Python? How to solve the problem of Pylance type detection of custom decorators in Python? Apr 02, 2025 am 06:42 AM

Pylance type detection problem solution when using custom decorator In Python programming, decorator is a powerful tool that can be used to add rows...

How to solve permission issues when using python --version command in Linux terminal? How to solve permission issues when using python --version command in Linux terminal? Apr 02, 2025 am 06:36 AM

Using python in Linux terminal...

Python 3.6 loading pickle file error ModuleNotFoundError: What should I do if I load pickle file '__builtin__'? Python 3.6 loading pickle file error ModuleNotFoundError: What should I do if I load pickle file '__builtin__'? Apr 02, 2025 am 06:27 AM

Loading pickle file in Python 3.6 environment error: ModuleNotFoundError:Nomodulenamed...

Do FastAPI and aiohttp share the same global event loop? Do FastAPI and aiohttp share the same global event loop? Apr 02, 2025 am 06:12 AM

Compatibility issues between Python asynchronous libraries In Python, asynchronous programming has become the process of high concurrency and I/O...

What should I do if the '__builtin__' module is not found when loading the Pickle file in Python 3.6? What should I do if the '__builtin__' module is not found when loading the Pickle file in Python 3.6? Apr 02, 2025 am 07:12 AM

Error loading Pickle file in Python 3.6 environment: ModuleNotFoundError:Nomodulenamed...

How to ensure that the child process also terminates after killing the parent process via signal in Python? How to ensure that the child process also terminates after killing the parent process via signal in Python? Apr 02, 2025 am 06:39 AM

The problem and solution of the child process continuing to run when using signals to kill the parent process. In Python programming, after killing the parent process through signals, the child process still...

See all articles