python io操作
一次性读取
1 # 读取文件
2
3 # 默认打开文件的方式是只读
4 file = None
5 try:
6 file = open("f:/test.sql")
7 print(file.name) # f:/test.sql
8
9 # read是一次性读取,调用read之后会把指针移动到文件的末尾,再次调用返回空字符串
10 content = file.read()
11
12 # print("----" + file.read())
13 print(content)
14 except Exception as log:
15 print("找不到文件")
16 finally:
17 if file:
18 file.close()
19
20 # 使用with语句,with语句会自动帮我们调用close()
21 with open("f:/test.sql") as f:
22 print(f.read())
23
24 # 使用with 可以创建单层级文件
25 # with open("f:/ooooooooooooooooa.sql","w") as f:
26 # f.write("asd")
逐行读取
1 # 逐行读取
2
3 file = None
4 try:
5 file = open("f:/test.sql")
6
7 line = file.readline()
8 while line is not None and line.strip() != "":
9 print(line)
10 line = file.readline()
11
12 except Exception as info:
13 print("文件未找到")
14 finally:
15 if file is not None:
16 file.close()
逐行读取并写入
1 # 逐行读取并写入
2 rs = None
3 ws = None
4 try:
5 rs = open("f:/test.sql")
6 ws = open("f:/test_copy.sql", "w")
7
8 # 读取并写入
9 while True:
10 line = rs.readline()
11
12 # 如果line为None或者line为空字符串
13 if line is None or line.strip() == "": # 或者 not line
14 break
15 ws.write(line)
16
17
18 except Exception as info:
19 print(info)
20 finally:
21 if rs:
22 rs.close()
23 if ws:
24 ws.close()
字节流
1 # -*- coding: utf-8 -*-
2 # @author: Tele
3 # @Time : 2019/04/04 下午 12:17
4 # 字节流读写
5 rs = open("F:/ftp_mypc/a.flv", "rb")
6 ws = open("f:/a_copy.flv", "wb")
7 buffer = 1024
8 while True:
9 content = rs.read(buffer)
10 if not content:
11 break
12 ws.write(content)
13
14 if rs:
15 rs.close()
16 if ws:
17 ws.close()
