#!/usr/bin/env python __author__ = "lrtao2010" #Python 3.7.0 字典常用方法 #字典的key是唯一的，且不能被修改，value可以是任意值 #字典是无序的 # info = {'name':'tom','age':'10'} # # info1 = { # 'name':'tom', # 'age':'10' # } # info = {'name':'tom','age':'10'} # v1 = info['name'] # v2 = info['age'] # # print(v1,v2) # tom 10 # info = { # 'name':[ # 11, # 22, # 33, # { # 'here':'ok' # } # # ] # } # # v = info['name'][3]['here'] # print(v) # ok #clear(self) 清空字典 # info = {"name":"tom"} # info.clear() # print(info) #copy(self) 浅复制 # info1 = {"name":['tom']} # info2 = info1.copy() # print(info2) # info1["name"][0] = 'lilei' # print(info1) # print(info2) # {'name': ['tom']} # {'name': ['lilei']} # {'name': ['lilei']} #深复制 # import copy # info1 = {"name":['tom']} # info2 = copy.deepcopy(info1) # print(info2) # info1["name"][0] = 'lilei' # print(info1) # print(info2) # {'name': ['tom']} # {'name': ['lilei']} # {'name': ['tom']} #fromkeys(*args, **kwargs)使用给定的键建立字典，默认对应值为None # keys_in = ('name','age') # keys_out1 = dict.fromkeys(keys_in) # keys_out2 = dict.fromkeys(keys_in,10) # print(keys_out1) # print(keys_out2) # {'name': None, 'age': None} # {'name': 10, 'age': 10} #get(self, *args, **kwargs) 返回指定键的值，如果键不存在，返回默认值 # info1 = {"name":['tom']} # print(info1.get('name','No')) # print(info1.get('name1','No')) # ['tom'] # No # v = info1['name1'] #键不存在会报异常 # print(v) # v = info1['name1'] # KeyError: 'name1' #items(self) 遍历键值对 # info1 = {"name":['tom']} # v = info1.items() # print(v) # dict_items([('name', ['tom'])]) #keys(self) 遍历键 # info1 = {"name":['tom']} # v1 = info1.keys() # print(v1) # dict_keys(['name']) #values(self) 遍历值 # info1 = {"name":['tom']} # v2 = info1.values() # print(v2) # dict_values([['tom']]) # info1 = {"name":['tom'],'age':'18','city':'BJ'} # # for k,v in info1.items(): # print("items()",k,v) # for k1 in info1.keys(): # print('keys()',k1) # for v1 in info1.values(): # print("values()",v1) # items() name ['tom'] # items() age 18 # items() city BJ # keys() name # keys() age # keys() city # values() ['tom'] # values() 18 # values() BJ #pop(self, k, d=None) # 删除指定的键，并返回值，要是键不存在，并且没有给定d值，报异常，给定d值，返回d值 # info1 = {"name":['tom'],'age':'18'} # v = info1.pop('name') # print(v) # print(info1) # ['tom'] # {'age': '18'} # info1 = {"name":['tom'],'age':'18'} # v = info1.pop('name1') # print(v) # print(info1) # v = info1.pop('name1') # KeyError: 'name1' # info1 = {"name":['tom'],'age':'18'} # v = info1.pop('name1','Not find') # print(v) # print(info1) # Not find # {'name': ['tom'], 'age': '18'} #popitem(self) 随机删除一个，并返回键值对 # info1 = {"name":['tom'],'age':'18','city':'BJ'} # v = info1.popitem() # print(v) # print(info1) # # ('city', 'BJ') # {'name': ['tom'], 'age': '18'} #setdefault(self, *args, **kwargs) #向字典中添加键值，如果添加的键在字典中不存在，直接加入键值，默认值为None # 键存在，则返回对应的值 # info1 = {"name":['tom']} # v1 = info1.setdefault('name','lei') # v2 = info1.setdefault('city') # v3 = info1.setdefault('age','18') # print(v1) # print(v2) # print(v3) # print(info1) # ['tom'] # None # 18 # {'name': ['tom'], 'city': None, 'age': '18'} #update(self, E=None, **F) 将字典2中的键值对更新到字典1中，要是有重复的键，将被覆盖 # info1 = {'name': ['tom'],'age': '18'} # info2 = {'name': ['lilei'], 'city': 'BJ'} # info1.update(info2) # print(info1) # print(info2) # {'name': ['lilei'], 'age': '18', 'city': 'BJ'} # {'name': ['lilei'], 'city': 'BJ'} # info1 = {'name': ['tom'],'age': '18'} # info1.update(name=123,city='SH') # print(info1) # {'name': 123, 'age': '18', 'city': 'SH'} # ################################################################## #删除k,v # info = {'name':'tom','age':'10'} # del info['age'] # print(info) # {'name': 'tom'}