• 7、字典的基本方法


    定义:ni = {  }

    创建字典:
    1
    2
    3
    person = {"name""mr.wu"'age'18}
    person = dict({"name""mr.wu"'age'18})

    常用操作:

    • 索引
    • 新增
    • 删除  del a[key]
    • 键、值、键值对
    • 循环    for i in 字典   输出的将是所有的key
    • 长度

    不能切片

    字典.items()可以获得所有的键值对 

    class dict(object):
        """
        dict() -> new empty dictionary
        dict(mapping) -> new dictionary initialized from a mapping object's
            (key, value) pairs
        dict(iterable) -> new dictionary initialized as if via:
            d = {}
            for k, v in iterable:
                d[k] = v
        dict(**kwargs) -> new dictionary initialized with the name=value pairs
            in the keyword argument list.  For example:  dict(one=1, two=2)
        """
    
        def clear(self): # real signature unknown; restored from __doc__
            """ 清除内容 """
            """ D.clear() -> None.  Remove all items from D. """
            pass
    
        def copy(self): # real signature unknown; restored from __doc__
            """ 浅拷贝 """
            """ D.copy() -> a shallow copy of D """
            pass
    
        @staticmethod # known case
        def fromkeys(S, v=None): # real signature unknown; restored from __doc__
            """
            dict.fromkeys(S[,v]) -> New dict with keys from S and values equal to v.
            v defaults to None.
            """
            pass
    
        def get(self, k, d=None): # real signature unknown; restored from __doc__
            """ 根据key获取值,d是默认值 """
            """ D.get(k[,d]) -> D[k] if k in D, else d.  d defaults to None. """
            pass
    
        def has_key(self, k): # real signature unknown; restored from __doc__
            """ 是否有key """
            """ D.has_key(k) -> True if D has a key k, else False """
            return False
    
        def items(self): # real signature unknown; restored from __doc__
            """ 所有项的列表形式 """
            """ D.items() -> list of D's (key, value) pairs, as 2-tuples """
            return []
    
        def iteritems(self): # real signature unknown; restored from __doc__
            """ 项可迭代 """
            """ D.iteritems() -> an iterator over the (key, value) items of D """
            pass
    
        def iterkeys(self): # real signature unknown; restored from __doc__
            """ key可迭代 """
            """ D.iterkeys() -> an iterator over the keys of D """
            pass
    
        def itervalues(self): # real signature unknown; restored from __doc__
            """ value可迭代 """
            """ D.itervalues() -> an iterator over the values of D """
            pass
    
        def keys(self): # real signature unknown; restored from __doc__
            """ 所有的key列表 """
            """ D.keys() -> list of D's keys """
            return []
    
        def pop(self, k, d=None): # real signature unknown; restored from __doc__
            """ 获取并在字典中移除 """
            """
            D.pop(k[,d]) -> v, remove specified key and return the corresponding value.
            If key is not found, d is returned if given, otherwise KeyError is raised
            """
            pass
    
        def popitem(self): # real signature unknown; restored from __doc__
            """ 获取并在字典中移除 """
            """
            D.popitem() -> (k, v), remove and return some (key, value) pair as a
            2-tuple; but raise KeyError if D is empty.
            """
            pass
    
        def setdefault(self, k, d=None): # real signature unknown; restored from __doc__
            """ 如果key不存在,则创建,如果存在,则返回已存在的值且不修改 """
            """ D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D """
            pass
    
        def update(self, E=None, **F): # known special case of dict.update   把新字典添加到当前字典中
            """ 更新
                {'name':'alex', 'age': 18000}
                [('name','sbsbsb'),]
            """
            """
            D.update([E, ]**F) -> None.  Update D from dict/iterable E and F.
            If E present and has a .keys() method, does:     for k in E: D[k] = E[k]
            If E present and lacks .keys() method, does:     for (k, v) in E: D[k] = v
            In either case, this is followed by: for k in F: D[k] = F[k]
            """
            pass
    
        def values(self): # real signature unknown; restored from __doc__
            """ 所有的值 """
            """ D.values() -> list of D's values """
            return []
    
        def viewitems(self): # real signature unknown; restored from __doc__
            """ 所有项,只是将内容保存至view对象中 """
            """ D.viewitems() -> a set-like object providing a view on D's items """
            pass
    
        def viewkeys(self): # real signature unknown; restored from __doc__
            """ D.viewkeys() -> a set-like object providing a view on D's keys """
            pass
    
        def viewvalues(self): # real signature unknown; restored from __doc__
            """ D.viewvalues() -> an object providing a view on D's values """
            pass
    
        def __cmp__(self, y): # real signature unknown; restored from __doc__
            """ x.__cmp__(y) <==> cmp(x,y) """
            pass
    
        def __contains__(self, k): # real signature unknown; restored from __doc__
            """ D.__contains__(k) -> True if D has a key k, else False """
            return False
    
        def __delitem__(self, y): # real signature unknown; restored from __doc__
            """ x.__delitem__(y) <==> del x[y] """
            pass
    
        def __eq__(self, y): # real signature unknown; restored from __doc__
            """ x.__eq__(y) <==> x==y """
            pass
    
        def __getattribute__(self, name): # real signature unknown; restored from __doc__
            """ x.__getattribute__('name') <==> x.name """
            pass
    
        def __getitem__(self, y): # real signature unknown; restored from __doc__
            """ x.__getitem__(y) <==> x[y] """
            pass
    
        def __ge__(self, y): # real signature unknown; restored from __doc__
            """ x.__ge__(y) <==> x>=y """
            pass
    
        def __gt__(self, y): # real signature unknown; restored from __doc__
            """ x.__gt__(y) <==> x>y """
            pass
    
        def __init__(self, seq=None, **kwargs): # known special case of dict.__init__
            """
            dict() -> new empty dictionary
            dict(mapping) -> new dictionary initialized from a mapping object's
                (key, value) pairs
            dict(iterable) -> new dictionary initialized as if via:
                d = {}
                for k, v in iterable:
                    d[k] = v
            dict(**kwargs) -> new dictionary initialized with the name=value pairs
                in the keyword argument list.  For example:  dict(one=1, two=2)
            # (copied from class doc)
            """
            pass
    
        def __iter__(self): # real signature unknown; restored from __doc__
            """ x.__iter__() <==> iter(x) """
            pass
    
        def __len__(self): # real signature unknown; restored from __doc__
            """ x.__len__() <==> len(x) """
            pass
    
        def __le__(self, y): # real signature unknown; restored from __doc__
            """ x.__le__(y) <==> x<=y """
            pass
    
        def __lt__(self, y): # real signature unknown; restored from __doc__
            """ x.__lt__(y) <==> x<y """
            pass
    
        @staticmethod # known case of __new__
        def __new__(S, *more): # real signature unknown; restored from __doc__
            """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
            pass
    
        def __ne__(self, y): # real signature unknown; restored from __doc__
            """ x.__ne__(y) <==> x!=y """
            pass
    
        def __repr__(self): # real signature unknown; restored from __doc__
            """ x.__repr__() <==> repr(x) """
            pass
    
        def __setitem__(self, i, y): # real signature unknown; restored from __doc__
            """ x.__setitem__(i, y) <==> x[i]=y """
            pass
    
        def __sizeof__(self): # real signature unknown; restored from __doc__
            """ D.__sizeof__() -> size of D in memory, in bytes """
            pass
    
        __hash__ = None
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  • 原文地址:https://www.cnblogs.com/liusiluandzhangkun/p/10229101.html
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