Python File readline() Method

Python File Methods

Overview

readline()This method is used to read a whole line from a file, including the "\n" character. If a non-negative parameter is specified, it returns bytes of the specified size, including the "\n" character.

Syntax

The syntax of the readline() method is as follows:

fileObject.readline(size)

Parameters

• size-- Number of bytes to read from the file.

Return Value

Returns the bytes read from the string.

Example

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

The contents of the file example.txt are as follows:

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

Loop through the file contents:

#!/usr/bin/python
# -*- coding: UTF-8 -*-

# 打开文件
fo = open("example.txt", "rw+")
print "文件名为: ", fo.name

line = fo.readline()
print "读取第一行 %s" % (line)

line = fo.readline(5)
print "读取的字符串为: %s" % (line)

# 关闭文件
fo.close()

The output of the above example is:

文件名为:  example.txt
读取第一行 1:www.example.com

读取的字符串为: 2:www

Python File Methods