python中不同的CSV功能和使用

在之前的文章中介绍过为什么python学习中会使用CSV文件格式？这边文章将会详细介绍python中不同的CSV功能和使用。

一、CSV模块功能

在CSV模块下，可以找到以下功能

二、Python中CSV文件操作

加载CSV文件后，您可以执行多种操作。将在Python中显示对CSV文件的读取和写入操作

在Python中读取CSV文件：

import csv 
 
with open('Titanic.csv','r') as csv_file: #Opens the file in read mode
    csv_reader = csv.reader(csv_file) # Making use of reader method for reading the file
 
    for line in csv_reader: #Iterate through the loop to read line by line
        print(line)

用Python写入CSV文件：

import csv 
with open('Titanic.csv', 'r') as csv_file:
    csv_reader = csv.reader(csv_file) 
    with open('new_Titanic.csv', 'w') as new_file: # Open a new file named 'new_titanic.csv' under write mode
        csv_writer = csv.writer(new_file, delimiter=';') #making use of write method
 
        for line in csv_reader: # for each file in csv_reader
            csv_writer.writerow(line) #writing out to a new file from each line of the original file

读取CSV文件作为字典

import csv 
 
with open('Titanic.csv','r') as csv_file: #Open the file in read mode
    csv_reader = csv.DictReader(csv_file) #use dictreader method to reade the file in dictionary
 
    for line in csv_reader: #Iterate through the loop to read line by line
        print(line)

作为字典写入CSV文件

import csv 
 
mydict = [{'Passenger':'1', 'Id':'0', 'Survived':'3'}, #key-value pairs as dictionary obj
          {'Passenger':'2', 'Id':'1', 'Survived':'1'},
          {'Passenger':'3', 'Id':'1', 'Survived':'3'}]
 
fields = ['Passenger', 'Id', 'Survived'] #field names
 filename = 'new_Titanic.csv' #name of csv file
 with open('new_Titanic.csv', 'w')as new_csv_file: #open a new file 'new_titanic,csv' under write mode
    writer = csv.DictWriter(new_csv_file, fieldnames=fields) 
    writer.writeheader() #writing the headers(field names)
 
    writer.writerows(mydict) #writing data rows