Home  >  Article  >  Backend Development  >  How to open a txt file in python

How to open a txt file in python

尚
Original
2019-07-03 09:20:4138143browse

How to open a txt file in python

Two ways to open files

f = open("data.txt","r")   #设置文件对象
f.close() #关闭文件


#为了方便,避免忘记close掉这个文件对象,可以用下面这种方式替代
with open('data.txt',"r") as f:    #设置文件对象
    str = f.read()    #可以是随便对文件的操作

Some simple operations on files:

1. Read files

1. Simply read the file into a string

f = open("data.txt","r")   #设置文件对象
str = f.read()     #将txt文件的所有内容读入到字符串str中
f.close()   #将文件关闭

2. Read the entire file line by line

#第一种方法
f = open("data.txt","r")   #设置文件对象
line = f.readline()
line = line[:-1]
while line:             #直到读取完文件
    line = f.readline()  #读取一行文件,包括换行符
    line = line[:-1]     #去掉换行符,也可以不去
f.close() #关闭文件


#第二种方法
data = []
for line in open("data.txt","r"): #设置文件对象并读取每一行文件
    data.append(line)               #将每一行文件加入到list中


#第三种方法
f = open("data.txt","r")   #设置文件对象
data = f.readlines()  #直接将文件中按行读到list里,效果与方法2一样
f.close()             #关闭文件

3. Read the file into an array

import numpy as np
data = np.loadtxt("data.txt")   #将文件中数据加载到data数组里

2 , write file

1. Simply write the string into txt

with open('data.txt','w') as f:    #设置文件对象
    f.write(str)                 #将字符串写入文件中

2. Write the list into the file

Single-layer list

data = ['a','b','c']
#单层列表写入文件
with open("data.txt","w") as f:
    f.writelines(data)

Double Layer list

#双层列表写入文件

#第一种方法,每一项用空格隔开,一个列表是一行写入文件
data =[ ['a','b','c'],['a','b','c'],['a','b','c']]
with open("data.txt","w") as f:                                                   #设置文件对象
    for i in data:                                                                 #对于双层列表中的数据
        i = str(i).strip('[').strip(']').replace(',','').replace('\'','')+'\n'  #将其中每一个列表规范化成字符串
        f.write(i)                                                                 #写入文件


#第二种方法,直接将每一项都写入文件
data =[ ['a','b','c'],['a','b','c'],['a','b','c']]
with open("data.txt","w") as f:                                                   #设置文件对象
    for i in data:                                                                 #对于双层列表中的数据
        f.writelines(i)                                                            #写入文件

For more Python related technical articles, please visit the Python Tutorial column to learn!

The above is the detailed content of How to open a txt file in python. For more information, please follow other related articles on the PHP Chinese website!

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