Python - file处理

 

 

"""
文件操作步骤：
1，打开文件
2，读
3，写
4，关闭文件 （写入的数据，临时保存在内存中，当关闭文件以后，才会从内存中存放到文件中）
"""



# f1 = open(r"D:\python\学习资料\test.txt",'w+')
# # f1 = open(r"D:\python\学习资料\test.txt",'w+',encoding="UTF-8 be")
# print(f1.read())
# f1.newlines
# f1.write("\n333")
# print(f1.read())
# f1.close()
#
# print("file path:{}".format(f1.name))
# print("file mode:{}".format(f1.mode))
# print("file status:{}".format(f1.closed))
#

# 如果出现IOError报错，可以使用try
"""
try:
    read, open,write
    
finally:
    close

"""


"""
作用：同try..finally..的效果一样
"""

# with open(r"D:\python\学习资料\test.txt",'r+') as f:
#     print(f.read())
    # f.write("111\n")
    # f.write("222\n")

# f = open(r"D:\python\学习资料\test2.txt",'r')
# f2 = open(r"D:\python\学习资料\test3.txt",'w')
# # f.write("111\n")
# # f.write("222\n")
# print(f.readline())
# position = f.tell()
# print(position)
# print("==============")
# position = f.seek(0,0)
# print(position)
# # print(f.read())
# f_text = f.read()
#
# f2.write(f_text)
#
# f.close()
# f2.close()
#
# print(f.closed)

"""
随堂测试：
1，接收用户输入的file
2，备份file -> file[备份]

"""

old_name = input("please input you backup file:")

index = old_name.rfind('.') # 找到这个字串对应的最后下标,找到就返回索引，找不到就返回-1

# 新文件名
new_name = old_name[:index] + "【备份】" + old_name[index:]

print(old_name)
print(new_name)

with open(old_name) as f:
    new_text = f.read()

print(new_text)
print(type(new_text))

if new_text == "":
    pass
else:
    with open(new_name, 'w+') as f2:
        f2.write(new_text)


***

# new class OS

# import OS

# mkdir,..... perform the function from OS.