python生成以及打开json、csv和txt文件的实例

mesg = "hello world"

with open("test.txt", "w") as f:
 f.write("{}".format(mesg))
 print("加载完成！")

import json


mesg = {"key": "value"}

with open("test.json", "w") as f:
 json.dump(mesg, f)
 print("加载完成！")

import csv


with open("test.csv", "w") as f:
 fieldnames = ["name", "age"] # 表的列名
 writer = csv.DictWriter(f, fieldnames=fieldnames)

 writer.writeheader() # 加上表头
 writer.writerow({"name": "shannon-li", "age": 4}) # 按行添加
 print("加载完成！")

with open("test.txt") as f:
 content = f.read()
 print("文件内容：{}".format(content))

import json
import sys


with open("test.json") as f:
 try:
  content = json.load(f)
  print("文件内容：{}".format(content))
 except TypeError:
  sys.exit("Error on load json file.")

import csv
import sys

content = []

with open("test.csv") as f:
 reader = csv.DictReader(f, delimiter=",", quotechar="|")

 try:
  for row in reader:
   content.append({"name": row["name"], "age": row["age"]})
  print("文件内容：".format(content))
 except csv.Error as e:
  sys.exit("file %s, line %d: %s" % (f, reader.line_num, e))