What is the Python File seek() method? How to understand and use it?

In today’s article, we will learn about the seek method in Python. Before entering the article, we must first know what pythonseek is, seek()Where can it be used in python programming and what role can it play. We can learn about these things in today’s article.

Overview

The seek() method is used to move the file reading pointer to the specified location.

Syntax

seek() method syntax is as follows:

fileObject.seek(offset[, whence])

Parameters

offset -- Start The offset, which represents the number of bytes that need to be moved.

whence: Optional, the default value is 0. Give the offset parameter a definition to indicate the position from which to start the offset; 0 means counting from the beginning of the file, 1 means counting from the current position, and 2 means counting from the end of the file.

Return value

This function has no return value.

Example

The following example demonstrates the use of the readline() method:

The content of the file runoob.txt is as follows:

1:www.runoob.com
2:www.runoob.com
3:www.runoob.com
4:www.runoob.com
5:www.runoob.com

Loop to read the contents of the file:

#!/usr/bin/python
# -*- coding: UTF-8 -*-
# 打开文件
fo = open("runoob.txt", "rw+")
print "文件名为: ", fo.name
line = fo.readline()
print "读取的数据为: %s" % (line)
# 重新设置文件读取指针到开头
fo.seek(0, 0)
line = fo.readline()
print "读取的数据为: %s" % (line)
# 关闭文件
fo.close()

The output result of the above example is:

文件名为:  runoob.txt
读取的数据为: 1:www.runoob.com
读取的数据为: 1:www.runoob.com

In this article, we understand what the seek() method is. If you understand, you can actually try it yourself. After all, hands-on practice is the best way to verify what you have learned. Finally, I hope this article can bring some help to you who are learning python.

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