Python文件操作

 1 #coding=utf-8
 2 
 3 oldFileName = input("请输入要拷贝的文件名字:")
 4 
 5 oldFile = open(oldFileName,‘r‘)
 6 
 7 # 如果打开文件
 8 if oldFile:
 9 
10     # 提取文件的后缀
11     fileFlagNum = oldFileName.rfind(‘.‘)
12     if fileFlagNum > 0:
13         fileFlag = oldFileName[fileFlagNum:]
14 
15     # 组织新的文件名字
16     newFileName = oldFileName[:fileFlagNum] + ‘[复件]‘ + fileFlag
17 
18     # 创建新文件
19     newFile = open(newFileName, ‘w‘)
20 
21     # 把旧文件中的数据，一行一行的进行复制到新文件中
22     for lineContent in oldFile.readlines():
23         newFile.write(lineContent)
24 
25     # 关闭文件
26     oldFile.close()
27     newFile.close()

 1     # 打开一个已经存在的文件
 2     f = open("test.txt", "r")
 3     str = f.read(30)
 4     print "读取的数据是 : ", str
 5 
 6     # 查找当前位置
 7     position = f.tell()
 8     print "当前文件位置 : ", position
 9 
10     # 重新设置位置
11     f.seek(5,0)
12 
13     # 查找当前位置
14     position = f.tell()
15     print "当前文件位置 : ", position
16 
17     f.close()

 1      #coding=utf-8
 2 
 3     # 批量在文件名前加前缀
 4 
 5     import os
 6 
 7     funFlag = 1 # 1表示添加标志  2表示删除标志
 8 
 9     folderName = ‘./renameDir/‘
10 
11     # 获取指定路径的所有文件名字
12     dirList = os.listdir(folderName)
13 
14     # 遍历输出所有文件名字
15     for name in dirList:
16         print name
17 
18         if funFlag == 1:
19             newName = ‘[东哥出品]-‘ + name
20         elif funFlag == 2:
21             num = len(‘[东哥出品]-‘)
22             newName = name[num:]
23         print newName
24 
25         os.rename(folderName+name, folderName+newName)

  1 #!/usr/bin/env python
  2 #!coding:utf-8
  3 #Author:Liuxiaoyang
  4 
  5 
  6 def login(username,password):
  7     flag=0
  8     with open(‘user.txt‘,‘r‘) as f:
  9         lines=f.readlines()
 10         for line in lines:
 11             if username==line.split(‘|‘)[0].strip() and password==line.split(‘|‘)[1].strip():
 12                 flag=1
 13                 print(‘hello world‘)
 14                 break
 15             else:
 16                 continue
 17         print(flag)
 18     if flag==0:
 19         return False
 20     else:
 21         return True
 22 
 23 def menu():
 24     while True:
 25         print("-"*50)
 26         print("Welcome to Info System v1.0")
 27         print("-"*50)
 28         print("1. browse(浏览)")
 29         print("2. find by id (通过身份证号查找信息)")
 30         print("3. find by name (通过姓名查找信息)")
 31         print("4. delete by id (通过身份证号删除信息)")
 32         print("5. update info (修改信息)")
 33         print("6. add info (新增信息)")
 34         print("7. quit (退出)")
 35         choice=int(input("Please input your choice: "))
 36         if choice==1:
 37             browse()
 38         if choice==2:
 39             find_by_id()
 40         if choice==3:
 41             find_by_name()
 42         if choice==4:
 43             delete_by_id()
 44         if choice==5:
 45             update()
 46         if choice==6:
 47             add_info()
 48         if choice==7:
 49             quit()
 50 
 51 
 52 def browse():
 53     with open(‘info.txt‘,‘r‘) as f:
 54         lines=f.readlines()
 55         for line in lines:
 56             print(line.strip())
 57 
 58 def find_by_name():
 59     name_input=input("Please input a name that you want to search : ")
 60     with open(‘info.txt‘,‘r‘) as f:
 61         lines=f.readlines()
 62         for line in lines:
 63             if line.split(‘-‘)[0].strip()==name_input:
 64                 print(‘*‘*50)
 65                 print(line.strip())
 66                 print(‘*‘*50)
 67                 break
 68             else:
 69                 continue
 70         else:
 71             print("No Userinfo that you want to search~")
 72 
 73 def find_by_id():
 74     id_input=input("Please input a id that you want to search : ")
 75     with open(‘info.txt‘,‘r‘) as f:
 76         lines=f.readlines()
 77         for line in lines:
 78             if line.split(‘-‘)[1].strip()==id_input:
 79                 print(‘*‘*50)
 80                 print(line.strip())
 81                 print(‘*‘*50)
 82                 break
 83             else:
 84                 continue
 85         else:
 86             print("No Userinfo that you want to search~")
 87 
 88 def delete_by_id():
 89     user_id=input("Please input an id that you want to delete : ")
 90     with open(‘info.txt‘,‘r+‘) as f1:
 91         lines=f1.readlines()
 92         for line in lines:
 93             if line.split(‘-‘)[1].strip()==user_id:
 94                 lines.remove(line)
 95     with open(‘info.txt‘,‘w‘) as f2:
 96         f2.writelines(lines)
 97     print("Delete successfully~")
 98 
 99 def update():
100     user_id=input("Please input an id that you want to update : ")
101     new_user_name=input("Please input a name that you want to update: ")
102     new_user_id=input("Please input an id that you want to upate: ")
103     with open(‘info.txt‘,‘r+‘) as f1:
104         lines=f1.readlines()
105         for line in lines:
106             if line.split(‘-‘)[1].strip()==user_id:
107                 lines.insert(lines.index(line),‘-‘.join((new_user_name,new_user_id))+‘\n‘)
108                 lines.remove(line)
109     with open(‘info.txt‘,‘w‘) as f2:
110         f2.writelines(lines)
111     print("Update successfully~")
112 
113 def add_info():
114     user_name=input("Please input your name that you want to add : ").strip()
115     user_id=input("Please input your id that you want to add : ").strip()
116     with open(‘info.txt‘,‘a‘) as f:
117         f.write(‘-‘.join((user_name,user_id))+‘\n‘)
118     print(‘Add new info successfully!‘)
119 
120 def quit():
121     ensure=input("Are you sure quit this system? y or n    :")
122     if ensure==‘y‘:
123         exit()
124     else:
125         menu()
126     
127 if __name__ == ‘__main__‘:
128     username=input("Please input your username : ").strip()
129     password=input("Please input your password : ").strip()
130     if login(username,password)==True:
131         print("Welcome")
132         menu()
133     else:
134         print("Discard")