dict方法
1 class dict(object): 2 """ 3 dict() -> new empty dictionary 4 dict(mapping) -> new dictionary initialized from a mapping object's 5 (key, value) pairs 6 dict(iterable) -> new dictionary initialized as if via: 7 d = {} 8 for k, v in iterable: 9 d[k] = v 10 dict(**kwargs) -> new dictionary initialized with the name=value pairs 11 in the keyword argument list. For example: dict(one=1, two=2) 12 """ 13 def clear(self): # real signature unknown; restored from __doc__ 14 """ D.clear() -> None. Remove all items from D. """ 15 pass 16 17 def copy(self): # real signature unknown; restored from __doc__ 18 """ D.copy() -> a shallow copy of D """ 19 pass 20 21 @staticmethod # known case 22 def fromkeys(*args, **kwargs): # real signature unknown 23 """ Create a new dictionary with keys from iterable and values set to value. """ 24 pass 25 26 def get(self, *args, **kwargs): # real signature unknown 27 """ Return the value for key if key is in the dictionary, else default. """ 28 pass 29 30 def items(self): # real signature unknown; restored from __doc__ 31 """ D.items() -> a set-like object providing a view on D's items """ 32 pass 33 34 def keys(self): # real signature unknown; restored from __doc__ 35 """ D.keys() -> a set-like object providing a view on D's keys """ 36 pass 37 38 def pop(self, k, d=None): # real signature unknown; restored from __doc__ 39 """ 40 D.pop(k[,d]) -> v, remove specified key and return the corresponding value. 41 If key is not found, d is returned if given, otherwise KeyError is raised 42 """ 43 pass 44 45 def popitem(self): # real signature unknown; restored from __doc__ 46 """ 47 D.popitem() -> (k, v), remove and return some (key, value) pair as a 48 2-tuple; but raise KeyError if D is empty. 49 """ 50 pass 51 52 def setdefault(self, *args, **kwargs): # real signature unknown 53 """ 54 Insert key with a value of default if key is not in the dictionary. 55 56 Return the value for key if key is in the dictionary, else default. 57 """ 58 pass 59 60 def update(self, E=None, **F): # known special case of dict.update 61 """ 62 D.update([E, ]**F) -> None. Update D from dict/iterable E and F. 63 If E is present and has a .keys() method, then does: for k in E: D[k] = E[k] 64 If E is present and lacks a .keys() method, then does: for k, v in E: D[k] = v 65 In either case, this is followed by: for k in F: D[k] = F[k] 66 """ 67 pass 68 69 def values(self): # real signature unknown; restored from __doc__ 70 """ D.values() -> an object providing a view on D's values """ 71 pass 72 73 def __contains__(self, *args, **kwargs): # real signature unknown 74 """ True if the dictionary has the specified key, else False. """ 75 pass 76 77 def __delitem__(self, *args, **kwargs): # real signature unknown 78 """ Delete self[key]. """ 79 pass 80 81 def __eq__(self, *args, **kwargs): # real signature unknown 82 """ Return self==value. """ 83 pass 84 85 def __getattribute__(self, *args, **kwargs): # real signature unknown 86 """ Return getattr(self, name). """ 87 pass 88 89 def __getitem__(self, y): # real signature unknown; restored from __doc__ 90 """ x.__getitem__(y) <==> x[y] """ 91 pass 92 93 def __ge__(self, *args, **kwargs): # real signature unknown 94 """ Return self>=value. """ 95 pass 96 97 def __gt__(self, *args, **kwargs): # real signature unknown 98 """ Return self>value. """ 99 pass 100 101 def __init__(self, seq=None, **kwargs): # known special case of dict.__init__ 102 """ 103 dict() -> new empty dictionary 104 dict(mapping) -> new dictionary initialized from a mapping object's 105 (key, value) pairs 106 dict(iterable) -> new dictionary initialized as if via: 107 d = {} 108 for k, v in iterable: 109 d[k] = v 110 dict(**kwargs) -> new dictionary initialized with the name=value pairs 111 in the keyword argument list. For example: dict(one=1, two=2) 112 # (copied from class doc) 113 """ 114 pass 115 116 def __iter__(self, *args, **kwargs): # real signature unknown 117 """ Implement iter(self). """ 118 pass 119 120 def __len__(self, *args, **kwargs): # real signature unknown 121 """ Return len(self). """ 122 pass 123 124 def __le__(self, *args, **kwargs): # real signature unknown 125 """ Return self<=value. """ 126 pass 127 128 def __lt__(self, *args, **kwargs): # real signature unknown 129 """ Return self<value. """ 130 pass 131 132 @staticmethod # known case of __new__ 133 def __new__(*args, **kwargs): # real signature unknown 134 """ Create and return a new object. See help(type) for accurate signature. """ 135 pass 136 137 def __ne__(self, *args, **kwargs): # real signature unknown 138 """ Return self!=value. """ 139 pass 140 141 def __repr__(self, *args, **kwargs): # real signature unknown 142 """ Return repr(self). """ 143 pass 144 145 def __setitem__(self, *args, **kwargs): # real signature unknown 146 """ Set self[key] to value. """ 147 pass 148 149 def __sizeof__(self): # real signature unknown; restored from __doc__ 150 """ D.__sizeof__() -> size of D in memory, in bytes """ 151 pass 152 153 __hash__ = None
1.clear()
清空字典
2.copy()
深拷贝父对象，浅拷贝子对象，
dict1 = {'a': 1,'b': 2,'c': [1,2]}
dict2 = dict1 # {'a': 1,'b': 2,'c': [1,2]}
dict3 = dict1.copy() #{'a': 1,'b': 2,'c': [1,2]}
dict1['c'][1] = 3
dict2 # {'a': 1,'b': 2,'c': [1,3]} 浅拷贝
dict3 # {'a': 1,'b': 2,'c': [1,2]} 深拷贝
3.fromkeys()
静态方法，该方法可返回一个新字典，fromkeys会接收两个参数，第一个参数为从外部传入的可迭代对象，会将循环取出元素作为字典的key值，另外一个参数是字典的value值，若这个值存在则所有的key值所对应的value值均为None，反之则为默认的值。
4.get()
返回字典中键为传参的值，若不存在这个键，则返回默认值，一般为None。
5.items()
返回一个可迭代的dict_items，其中为所有的键值对，每一对都以元组形式保存。
6.keys()
返回一个可迭代的dict_keys，其中为字典中的所有键
7.pop()
参数为想要删除的键名，返回该键所对应的的值，当字典为空时，调用此方法，会产生异常。
8.popitem()
随机返回并删除字典中的最后一对键和值。当字典为空时，调用此方法，会产生异常。
9.setdefault()
如果字典中包含有给定键，则返回该键对应的值，否则返回为该键设置的值
10.update()
更新字典，把传入字典添加到本字典中。
11.values()
返回一个可迭代的dict_values，其中为字典中的所有值
12.dict中的内置函数
__contains__ 确认字典中是否包含这个键 __delitem__ 删除 del dict[key] __eq__ 判断是否相同 __getattribute__ 获取字典的属性 __getitem__ 返回值 __ge__ 判断值是否大于 __iter__ 可迭代 __len__ 返回字典长度 len(dict) __le__ 判断值是否小于等于 __lt__ 判断值是否小于 __new__ 新建并返回一个字典对象 dict() __ne__ 判断值是否不同 __repr__ 直接输出时的内容 __setitem__ 设置对应键的值 dict[key] = value __sizeof__ 查看字典所占内存
