1 with open("小重山","r",encoding="utf-8") as f:
2     data = f.read()
3     print(data)
4     f.close()

1 with open("小重山","r",encoding="utf-8") as f:
2     data = f.readlines()
3     for i in data:
4         print(i.strip())
5
6 with open("小重山1","w",encoding="utf-8") as f:
7     f.write("昨夜寒蛩不住鸣。惊回千里梦，已三更。起来独自绕阶行。")

 1 with open("小重山","r",encoding="utf-8") as f:
 2     # print(f.fileno()) #文件句柄 #3
 3     num1 = 0
 4     for i in f.readlines():
 5         num1 += 1
 6         if num1 == 6:
 7             i = ''.join([i.strip(),'ok'])
 8         print(i.strip())
 9
10 with open("小重山","r",encoding="utf-8") as f:
11     num1 = 0
12     for i in f:  #for循环内部将f 对象做成一个迭代器，用一行取一行
13         num1 += 1
14         if num1 == 4:
15             i = "".join([i.strip(),"ok"])
16         print(i.strip())

 1 import time,sys
 2
 3 for i in range(30):
 4     sys.stdout.write("*")
 5     time.sleep(0.2)
 6     sys.stdout.flush()
 7
 8 for i in range(30):
 9     print("*",end="",flush=True)
10     time.sleep(0.2)

1 with open("小重山1","a",encoding="utf-8") as f:
2     f.truncate(6) #昨夜

1 with open("小重山1","a+",encoding="utf-8") as f:
2     f.write("岳飞") #写入文件最后
3     f.close()

1 with open("小重山1","w+",encoding="utf-8") as f:
2     f.write("岳飞")
3     print(f.tell()) #6
4     f.seek(0)
5     print(f.readline())

1 with open("小重山1","a+",encoding="utf-8") as f:
2     print(f.tell())
3     f.write("岳飞")
4     print(f.tell())
5     print(f.readline())

 1 # f_read = open("小重山1",'r',encoding="utf-8")
 2 # f_write = open("小重山2",'w',encoding="utf-8")
 3 #with 同时管理多个文件对象
 4 with open("小重山1",'r',encoding="utf-8") as f_read,open("小重山2",'w',encoding="utf-8") as f_write:
 5     num1 = 0
 6     for line in f_read:
 7         num1 += 1
 8         if num1 == 5:
 9             line = "".join([line.strip(),"dream\n"])
10         f_write.write(line)
11         print(line.strip())
12     f_write.close()
13     f_read.close()