Python文件的四种读写方式——r a w r+

# 文件的基本操作，但是一般不这么使用，因为经常会忘记关闭
password=open("abc.txt",mode="r",encoding="UTF-8")
print(password)
fileContentn=password.read()
print(fileContentn)
print(password.closed)
password.close()
print(password.closed)
print()
# 为了解决经常忘记关闭文件，使用with open() as 文件命名： 会自动关闭文件

# mode="a"在文件的后面添加数据
with open("abc.txt",mode="a",encoding="UTF-8") as abc:
    abc.write("\nHello\n")
# mode="r"读取数据
with open("abc.txt",mode="r",encoding="UTF-8") as abc:
    fileContent=abc.read()
    print(fileContent)

# mode="w" 清除文件内容，进行重新输入值
with open("abc.txt",mode="w",encoding="UTF-8") as abc:
    abc.write("I clear all！")

# mode="r"读取数据
with open("abc.txt",mode="r",encoding="UTF-8") as abc:
    fileContent=abc.read()
    print(fileContent)

# mode="r+"皆可以读写
with open("abc.txt", mode="r+") as abc:
    print(abc.tell())
    abc.write("r+ comes to try!")
    print(abc.tell())
    print(abc.read())