Python网络编程（一）

 1 # 打开文件
 2 try:
 3   fd = open(‘img.jpg‘,‘ab+‘)
 4 except FileNotFoundError as e:
 5   print(e)
 6 
 7 # 开始你的读写
 8 
 9 # 关闭文件
10 fd.close()

 1 # 打开文件
 2 f = open(‘test‘,‘r‘)
 3 
 4 #　read循环读取文件
 5 while True:
 6   #　一次最多读取1024字节
 7   data = f.read(1024)
 8   #　读到文件结尾得到空字符串，此时跳出循环
 9   if not data:
10     break
11   print("读取的内容:",data)

1 # 打开文件
2 f = open(‘test‘,‘r‘)
3 
4 #　读取一行内容
5 data = f.readline()
6 print("读取的内容:",data)
7 data = f.readline()
8 print("读取的内容:",data)

1 # 打开文件
2 f = open(‘test‘,‘r‘)
3 
4 #　读取所有内容，每行作为列表中一个元素
5 data = f.readlines()
6 print("读取的内容:",data)

1 # 打开文件
2 f = open(‘test‘,‘r‘)
3 #    每次获取文件一行
4 for line in f:
5      print(line)

1 # w原有内容被清除,a则追加
2 #f = open(‘test‘,‘a‘)
3 f = open(‘test‘,‘wb‘)
4 #　如果是wb打开要转换为字节串写入
5 f.write("hello word\n".encode())
6 f.write("python".encode())
7 
8 f.close()

1 # w原有内容被清除,a则追加
2 f = open(‘test‘,‘a‘)
3 
4 f.writelines([‘abc\n‘,‘def\n‘])
5 
6 f.close()

1 with open(‘file‘,‘r+‘) as f:
2     f.read()
3 等同于----------------------
4 f=open(‘file’，‘r+’)
5 f.read()
6 f.close()

a                indef art one
abandonment      n.  abandoning
abashed          adj. ~ embarrassed; ashamed
abate            v. make or become less
abattoir         n. = slaughterhouse (slaughter)
abbess           n. woman who is head of a convent or nunnery
abbot            n. man who is head of a monastery or abbey
abbreviate       v. ~ sth shorten (a word, phrase, etc), esp by omitting letters
abbreviation     n.  abbreviating or being abbreviated
abdicate         v.  resign from or formally renounce the throne
abdication       giving up control, authority
abdominal        adj. in, of or for the abdomen
abduct           v. take away illegally, using force or deception; kidnap ;
abduction        A carrying away of a person against his will, or illegally.
abed             In bed; on a bed.
aberrant         adj. not following the normal or correct way
aberration       n.  deviation from what is accepted as normal or right
abhor            v. feel hatred and disgust for (sb/sth); detest
abhorrence       n. hatred and disgust
profligacy       n. being profligate
profligate       adj.  recklessly extravagant or wasteful
profound         adj.  deep, intense or far-reaching; verygreat
profoundly       adv. deeply; extremely
profundity       n.  depth (esp of knowledge, thought, etc)
profuse          adj.  in large amounts; abundant
profusion        n.  ~ of sth abundant supply of sth
progenitor       n.  ancestor (of a person, an animal or a plant)
progeny          n. offspring
prognosticate    v.  tell (sth) in advance; predict

 1 word = input("Word:")
 2 
 3 #　默认ｒ打开
 4 f = open("dict.txt")
 5 
 6 for line in f:
 7   tmp = line.split(‘ ‘)[0]
 8   #　遍历的单词已经大于目标
 9   if tmp > word:
10     print("没有找到该单词")
11     break
12   elif tmp == word:
13     print(line)
14     break
15 else:
16   print("没有找到该单词")
17 
18 f.close()

 1 """
 2 缓冲区
 3 """
 4 
 5 #　１表示行缓冲
 6 f = open(‘test‘,‘w‘,1)
 7 
 8 while True:
 9   s = input(">>")
10   f.write("nihao\n")
11   # f.flush() # 将缓冲内容写入磁盘
12 
13 f.close()

 1 # r,w打开文件偏移量在开头
 2 # a打开文件偏移量在结尾
 3 f = open(‘test‘,‘wb+‘)
 4 
 5 f.write(b"hello\n")
 6 f.flush()
 7 
 8 print(f.tell())  #打印当前文件偏移量
 9 f.seek(-3,2)  #　以开头为基准向后移动０字节
10 
11 data = f.read()
12 print(data)

1 f = open(‘test‘,‘wb‘)
2 
3 f.write(b‘start‘)
4 f.seek(1000,2) # 结尾位置向后移动１０００字节
5 f.write(b‘end‘)
6 
7 f.close()

 1 import time
 2 
 3 f = open(‘log.txt‘,‘a+‘)
 4 
 5 n = 0
 6 f.seek(0,0) # 将偏移量移动待开始然后计数
 7 for line in f:
 8   n += 1
 9 
10 while True:
11   n += 1
12   time.sleep(1)
13   s = "%d.  %s\n"%(n,time.ctime())
14   f.write(s)
15   f.flush()  #　随时看到文件变化

 1 #　输入文件名
 2 filename = input("File:")
 3 
 4 try:
 5   fr = open(filename,‘rb‘)
 6 except FileNotFoundError as e:
 7   print(e)
 8 else:
 9   fw = open(‘file.jpg‘,‘wb‘)
10 
11   #　循环复制
12   while True:
13     data = fr.read(1024)
14     if not data:
15       break
16     fw.write(data)
17 
18   fr.close()
19   fw.close()