python开发_shelve_完整版_博主推荐
''' 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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1 #python shelve 2 3 #Author : Hongten 4 #MailTo : hongtenzone@foxmail.com 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()
