python生成以及打开json、csv和txt文件

生成txt文件：

mesg = "hello world"

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

生成json文件：

import json


mesg = {"key": "value"}

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

生成csv文件：

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！")

打开txt文件：

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

打开json文件：

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.")

打开csv文件：

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))