''' 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... >>>
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代码部分：
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#python shelve #Author : Hongten #MailTo : hongtenzone@foxmail.com #QQ : 648719819 #Blog : http://www.cnblogs.com/hongten #Create : 2013-08-09 #Version: 1.0 import shelve ''' 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(). #################################################### ''' #global var #是否显示日志信息 SHOW_LOG = True def get_shelve(): '''open -- file may get suffix added by low-level library''' return shelve.open('c:\test\hongten.dat', 'c') def save(sh): '''保存数据''' if sh is not None: sh['name'] = 'Hongten' sh['gender'] = 'M' sh['address'] = {'hometown' : 'Shuifu,Yunnan', 'nowadd' : 'Guangzhou,Guangdong'} sh['phone'] = ('13423****62', '18998****62') sh['age'] = 22 if SHOW_LOG: for item in sh.items(): print('保存数据[{}] = [{}]'.format(item[0], sh[item[0]])) sh.close() else: print('the shelve object is None!') def update(sh): '''更新数据''' if sh is not None: sh['name'] = 'Hongten' sh['hoby'] = ('篮球', '羽毛球', '乒乓球', '游泳') sh['phone'] = ('13423****62', '18998****62', '020-90909090') sh['age'] = 23 if SHOW_LOG: keys = ('name', 'hoby', 'phone', 'age') for item in keys: print('更新数据[{}] = [{}]'.format(item, sh[item])) sh.close() else: print('the shelve object is None!') def delete(sh, key): '''删除某个数据''' if sh is not None: if SHOW_LOG: print('删除[{}]的数据'.format(key)) del sh[key] sh.close() else: print('the shelve object is None!') def deleteall(sh): '''删除所有数据''' if sh is not None: for item in sh.items(): if SHOW_LOG: print('删除数据[{}] = [{}]'.format(item[0], sh[item[0]])) del sh[item[0]] sh.close() else: print('the shelve object is None!') def fetchone(sh, key): '''获取某个数据''' if sh is not None: print('获取[{}]的值：{}'.format(key, sh[key])) sh.close() else: print('the shelve object is None!') def fetchall(sh): '''遍历所有数据''' if sh is not None: for item in sh.items(): print('数据[{}] = [{}]'.format(item[0], sh[item[0]])) sh.close() else: print('the shelve object is None!') ############################################################### ### 测试 START ############################################################### def save_test(): '''保存数据...''' print('保存数据...') sh = get_shelve() save(sh) def fetchall_test(): '''遍历所有数据''' print('遍历所有数据...') sh = get_shelve() fetchall(sh) def fetchone_test(): '''获取某个数据''' print('获取某个数据...') sh = get_shelve() key = 'address' fetchone(sh, key) def delete_test(): '''删除某个数据''' print('删除某个数据...') sh = get_shelve() key = 'hoby' delete(sh, key) def update_test(): '''更新数据...''' print('更新数据...') sh = get_shelve() update(sh) def deleteall_test(): '''删除所有数据''' print('删除所有数据...') sh = get_shelve() deleteall(sh) ############################################################### ### 测试 END ############################################################### def init(): global SHOW_LOG SHOW_LOG = True print('SHOW_LOG : {}'.format(SHOW_LOG)) deleteall_test() save_test() def main(): init() print('#' * 50) fetchall_test() print('#' * 50) update_test() print('#' * 50) fetchall_test() print('#' * 50) fetchone_test() print('#' * 50) delete_test() print('#' * 50) fetchall_test() print('#' * 50) deleteall_test() print('#' * 50) fetchall_test() if __name__ == '__main__': main()