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  • 1.3

     1 # 1.循环遍历所有得key
     2 dic = {'K1': 'v1', 'K2': 'v2', 'K3': 'v3'}
     3 
     4 print(dic)
     5 
     6 for i in dic.keys():
     7     print(i)
     8 
     9 # 2.循环遍历所有得value
    10 for j in dic.values():
    11     print(j)
    12 
    13 # 3.循环遍历所有得key和value
    14 for k, v in dic.items():   //这种方法不用效率低
    15     print(k, v)
    16 for k in dic:
    17     print(k,dic[k])
    18 
    19 # 4.添加键值对 并输出
    20 dic['K4'] = 'v4'
    21 print(dic)
    22 
    23 # 5.删除了K1键值对
    24 dic.pop('K1')
    25 del dic['K1']
    26 print(dic)
    27 
    28 # 6.删除K5 不存在返回 None
    29 result = dic.get('K5')
    30 if result != None:
    31     dic.pop('K5')
    32 else:
    33     print(result)
    34 
    35 # 7.获取字典中 K2对应得值
    36 # result = dic['K2']
    37 result = dic.get('K2')
    38 print(result) 
    39 
    40 # 8.获取K6不存在返回None
    41 result = dic.get('K6')
    42 print(result)
    43 
    44 # 9.dic2 更新 被dic
    45 dic2 = {'K1': 'v111', 'a': 'b'}
    46 print(dic,dic2)
    47 dic2.update(dic)
    48 print(dic,dic2)
    49 
    50 # 10.列表 字典 嵌套
    51 Lis = ['k',['qwe',20,{'k1':['tt',3,'1']},89],'ab']
    52 print(Lis)
    53 
    54 # Lis[1][2].get('k1')[0] = 'TT'
    55 Lis[1][2].get('k1')[0] = Lis[1][2].get('k1')[0].upper()
    56 print(Lis)
    57 
    58 Lis[1][2].get('k1')[1] = '100'
    59 print(Lis)
    60 
    61 Lis[1][2].get('k1')[-1] = 101
    62 print(Lis)
    63 
    64 # 11.将列表得奇数位 添加到字典中 
    65 li = [1, 2, 3, 'a', 'b', 4, 'c']
    66 dic = {}
    67 dic.setdefault('K1',[])
    68 for index, i in enumerate(li):
    69     if index % 2 == 1:
    70         dic['K1'].append(i)
    71 
    72 print(dic)
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  • 原文地址:https://www.cnblogs.com/alice-bj/p/8427421.html
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