python开发_shelve_完整版

'''

    python中的shelve模块，可以提供一些简单的数据操作

    他和python中的dbm很相似。



    区别如下：

    都是以键值对的形式保存数据，不过在shelve模块中，

    key必须为字符串，而值可以是python所支持的数据

    类型。在dbm模块中，键值对都必须为字符串类型。



    sh['a'] = 'a'

    sh['c'] = [11, 234, 'a']

    sh['t'] = ('1', '2', '3')

    sh['d'] = {'a':'2', 'name':'Hongte' }

    sh['b'] = 'b'

    sh['i'] = 23



    我们可以获取一个shelve对象

    sh = shelve.open('c:\\test\\hongten.dat', 'c')



    删除shelve对象中的某个键值对

    del sh['d']



    遍历所有数据

    for item in sh.items():

        print('键[{}] = 值[{}]'.format(item[0], sh[item[0]]))



    获取某个键值对

    print(sh['a'])



    关闭shelve对象:

    sh.close()

    

    ####################################################

    ####        API中强调

    Do not rely on the shelf being closed automatically;

    always call close() explicitly when you don’t need

    it any more, or use a with statement with

    contextlib.closing().

    ####################################################



'''

下面是我做的demo，在demo中我做了比较详细的注释和说明，详情如下：

运行效果：

SHOW_LOG = False

Python 3.3.2 (v3.3.2:d047928ae3f6, May 16 2013, 00:03:43) [MSC v.1600 32 bit (Intel)] on win32

Type "copyright", "credits" or "license()" for more information.

>>> ================================ RESTART ================================

>>> 

SHOW_LOG : False

删除所有数据...

保存数据...

##################################################

遍历所有数据...

数据[gender] = [M]

数据[phone] = [('13423****62', '18998****62')]

数据[age] = [22]

数据[name] = [Hongten]

数据[address] = [{'hometown': 'Shuifu,Yunnan', 'nowadd': 'Guangzhou,Guangdong'}]

##################################################

更新数据...

##################################################

遍历所有数据...

数据[gender] = [M]

数据[phone] = [('13423****62', '18998****62', '020-90909090')]

数据[name] = [Hongten]

数据[hoby] = [('篮球', '羽毛球', '乒乓球', '游泳')]

数据[age] = [23]

数据[address] = [{'hometown': 'Shuifu,Yunnan', 'nowadd': 'Guangzhou,Guangdong'}]

##################################################

获取某个数据...

获取[address]的值：{'hometown': 'Shuifu,Yunnan', 'nowadd': 'Guangzhou,Guangdong'}

##################################################

删除某个数据...

##################################################

遍历所有数据...

数据[gender] = [M]

数据[phone] = [('13423****62', '18998****62', '020-90909090')]

数据[age] = [23]

数据[name] = [Hongten]

数据[address] = [{'hometown': 'Shuifu,Yunnan', 'nowadd': 'Guangzhou,Guangdong'}]

##################################################

删除所有数据...

##################################################

遍历所有数据...

>>> 

SHOW_LOG = True

Python 3.3.2 (v3.3.2:d047928ae3f6, May 16 2013, 00:03:43) [MSC v.1600 32 bit (Intel)] on win32

Type "copyright", "credits" or "license()" for more information.

>>> ================================ RESTART ================================

>>> 

SHOW_LOG : True

删除所有数据...

保存数据...

保存数据[age] = [22]

保存数据[gender] = [M]

保存数据[address] = [{'hometown': 'Shuifu,Yunnan', 'nowadd': 'Guangzhou,Guangdong'}]

保存数据[phone] = [('13423****62', '18998****62')]

保存数据[name] = [Hongten]

##################################################

遍历所有数据...

数据[age] = [22]

数据[name] = [Hongten]

数据[gender] = [M]

数据[address] = [{'hometown': 'Shuifu,Yunnan', 'nowadd': 'Guangzhou,Guangdong'}]

数据[phone] = [('13423****62', '18998****62')]

##################################################

更新数据...

更新数据[name] = [Hongten]

更新数据[hoby] = [('篮球', '羽毛球', '乒乓球', '游泳')]

更新数据[phone] = [('13423****62', '18998****62', '020-90909090')]

更新数据[age] = [23]

##################################################

遍历所有数据...

数据[age] = [23]

数据[gender] = [M]

数据[address] = [{'hometown': 'Shuifu,Yunnan', 'nowadd': 'Guangzhou,Guangdong'}]

数据[hoby] = [('篮球', '羽毛球', '乒乓球', '游泳')]

数据[phone] = [('13423****62', '18998****62', '020-90909090')]

数据[name] = [Hongten]

##################################################

获取某个数据...

获取[address]的值：{'hometown': 'Shuifu,Yunnan', 'nowadd': 'Guangzhou,Guangdong'}

##################################################

删除某个数据...

删除[hoby]的数据

##################################################

遍历所有数据...

数据[age] = [23]

数据[name] = [Hongten]

数据[gender] = [M]

数据[address] = [{'hometown': 'Shuifu,Yunnan', 'nowadd': 'Guangzhou,Guangdong'}]

数据[phone] = [('13423****62', '18998****62', '020-90909090')]

##################################################

删除所有数据...

删除数据[age] = [23]

删除数据[gender] = [M]

删除数据[address] = [{'hometown': 'Shuifu,Yunnan', 'nowadd': 'Guangzhou,Guangdong'}]

删除数据[phone] = [('13423****62', '18998****62', '020-90909090')]

删除数据[name] = [Hongten]

##################################################

遍历所有数据...

>>> 

=====================================================

代码部分：

=====================================================

  1 #python shelve

  2 

  3 #Author : Hongten

  4 #MailTo : [email protected]

  5 #QQ     : 648719819

  6 #Blog   : http://www.cnblogs.com/hongten

  7 #Create : 2013-08-09

  8 #Version: 1.0

  9 

 10 import shelve

 11 '''

 12     python中的shelve模块，可以提供一些简单的数据操作

 13     他和python中的dbm很相似。

 14 

 15     区别如下：

 16     都是以键值对的形式保存数据，不过在shelve模块中，

 17     key必须为字符串，而值可以是python所支持的数据

 18     类型。在dbm模块中，键值对都必须为字符串类型。

 19 

 20     sh['a'] = 'a'

 21     sh['c'] = [11, 234, 'a']

 22     sh['t'] = ('1', '2', '3')

 23     sh['d'] = {'a':'2', 'name':'Hongte' }

 24     sh['b'] = 'b'

 25     sh['i'] = 23

 26 

 27     我们可以获取一个shelve对象

 28     sh = shelve.open('c:\\test\\hongten.dat', 'c')

 29 

 30     删除shelve对象中的某个键值对

 31     del sh['d']

 32 

 33     遍历所有数据

 34     for item in sh.items():

 35         print('键[{}] = 值[{}]'.format(item[0], sh[item[0]]))

 36 

 37     获取某个键值对

 38     print(sh['a'])

 39 

 40     关闭shelve对象:

 41     sh.close()

 42     

 43     ####################################################

 44     ####        API中强调

 45     Do not rely on the shelf being closed automatically;

 46     always call close() explicitly when you don’t need

 47     it any more, or use a with statement with

 48     contextlib.closing().

 49     ####################################################

 50 

 51 '''

 52 #global var

 53 #是否显示日志信息

 54 SHOW_LOG = True

 55 

 56 def get_shelve():

 57     '''open -- file may get suffix added by low-level library'''

 58     return shelve.open('c:\\test\\hongten.dat', 'c')

 59 

 60 def save(sh):

 61     '''保存数据'''

 62     if sh is not None:

 63         sh['name'] = 'Hongten'

 64         sh['gender'] = 'M'

 65         sh['address'] = {'hometown' : 'Shuifu,Yunnan', 'nowadd' : 'Guangzhou,Guangdong'}

 66         sh['phone'] = ('13423****62', '18998****62')

 67         sh['age'] = 22

 68         if SHOW_LOG:

 69             for item in sh.items():

 70                 print('保存数据[{}] = [{}]'.format(item[0], sh[item[0]]))

 71         sh.close()

 72     else:

 73         print('the shelve object is None!')

 74 

 75 def update(sh):

 76     '''更新数据'''

 77     if sh is not None:

 78         sh['name'] = 'Hongten'

 79         sh['hoby'] = ('篮球', '羽毛球', '乒乓球', '游泳')

 80         sh['phone'] = ('13423****62', '18998****62', '020-90909090')

 81         sh['age'] = 23

 82         if SHOW_LOG:

 83             keys = ('name', 'hoby', 'phone', 'age')

 84             for item in keys:

 85                 print('更新数据[{}] = [{}]'.format(item, sh[item]))

 86         sh.close()

 87     else:

 88         print('the shelve object is None!')

 89 

 90 def delete(sh, key):

 91     '''删除某个数据'''

 92     if sh is not None:

 93         if SHOW_LOG:

 94             print('删除[{}]的数据'.format(key))

 95         del sh[key]

 96         sh.close()

 97     else:

 98         print('the shelve object is None!')

 99 

100 def deleteall(sh):

101     '''删除所有数据'''

102     if sh is not None:

103         for item in sh.items():

104             if SHOW_LOG:

105                 print('删除数据[{}] = [{}]'.format(item[0], sh[item[0]]))

106             del sh[item[0]]

107         sh.close()

108     else:

109         print('the shelve object is None!')

110 

111 def fetchone(sh, key):

112     '''获取某个数据'''

113     if sh is not None:

114         print('获取[{}]的值：{}'.format(key, sh[key]))

115         sh.close()

116     else:

117         print('the shelve object is None!')

118 

119 def fetchall(sh):

120     '''遍历所有数据'''

121     if sh is not None:

122         for item in sh.items():

123             print('数据[{}] = [{}]'.format(item[0], sh[item[0]]))

124         sh.close()

125     else:

126         print('the shelve object is None!')

127 

128 ###############################################################

129 ###                测试           START

130 ###############################################################

131 def save_test():

132     '''保存数据...'''

133     print('保存数据...')

134     sh = get_shelve()

135     save(sh)

136 

137 def fetchall_test():

138     '''遍历所有数据'''

139     print('遍历所有数据...')

140     sh = get_shelve()

141     fetchall(sh)

142 

143 def fetchone_test():

144     '''获取某个数据'''

145     print('获取某个数据...')

146     sh = get_shelve()

147     key = 'address'

148     fetchone(sh, key)

149 

150 def delete_test():

151     '''删除某个数据'''

152     print('删除某个数据...')

153     sh = get_shelve()

154     key = 'hoby'

155     delete(sh, key)

156 

157 def update_test():

158     '''更新数据...'''

159     print('更新数据...')

160     sh = get_shelve()

161     update(sh)

162 

163 def deleteall_test():

164     '''删除所有数据'''

165     print('删除所有数据...')

166     sh = get_shelve()

167     deleteall(sh)

168     

169 ###############################################################

170 ###                测试           END

171 ###############################################################

172 

173 def init():

174     global SHOW_LOG

175     SHOW_LOG = True

176     print('SHOW_LOG : {}'.format(SHOW_LOG))

177     deleteall_test()

178     save_test()

179 

180 def main():

181     init()

182     print('#' * 50)

183     fetchall_test()

184     print('#' * 50)

185     update_test()

186     print('#' * 50)

187     fetchall_test()

188     print('#' * 50)

189     fetchone_test()

190     print('#' * 50)

191     delete_test()

192     print('#' * 50)

193     fetchall_test()

194     print('#' * 50)

195     deleteall_test()

196     print('#' * 50)

197     fetchall_test()

198     

199 if __name__ == '__main__':

200     main()