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))