python
# python中的列表# 定义列表的方法# list1 = ["dcs","xian03",10086,["10010"]]
# print(list1) #['dcs', 'xian03', 10086, ['10010']]
# print(type(list1)) #<class 'list'>
# str1 = "xian03"
# list1 = list(str1)
# print(list1) #['x', 'i', 'a', 'n', '0', '3']
# 列表中常用的函数和用法
# 1.索引赋值
# list1 = ["dcs","xian",10086,["10010"]]
# list1 = "duoceshi" #把索引为0的"dcs"赋值为"duoceshi"
# print(list1) #['duoceshi', 'xian', 10086, ['10010']]
# 2.切片赋值
# list1 = ["dcs","xian",10086,["10010"]]
# list1 = "hello" #把索引为1,2的"xian",10086,切片赋值为hello
# print(list1) #['dcs', 'h', 'e', 'l', 'l', 'o', ['10010']]
# 列表中的函数
# 1.append():添加元素到列表中，显示在列表最末段.可以添加任何数据类型的元素
# list1 = ["dcs","xian",10086,"10010"]
# list1.append("10086") #添加一个字符串"10086"
# print(list1) # ['dcs', 'xian', 10086, '10010', '10086']]
# 2.insert():根据索引位置给列表插入元素
# list1 = ["dcs","xian",10086,"10010"]
# list1.insert(2,"10086") #添加一个字符串"10086"
# print(list1) #['dcs', 'xian', '10086', 10086, '10010']
# 3.extend():连接两个列表整合成一个列表，还可以拼接字符串
# 列表链接列表
# list1 = ["dcs","xian"]
# list2 =
# list1.extend(list2)
# print(list1) #['dcs', 'xian', 10086, '10010']
# 列表链接字符串
# list1 = ["dcs","xian"]
# str1 = "dcs"
# list1.extend(str1)
# print(list1) #['dcs', 'xian', 'd', 'c', 's']
# 列表链接整型,不能进行拼接
# list1 = ["dcs","xian"]
# int1 = 123
# list1.extend(int1)
# print(list1) #TypeError: 'int' object is not iterable
# 4.remove() 移除列表中元素，根据元素删除
# list2 = ["dcs","xian",10086,10086,"10010"]
# list2.remove(10086) #如果有重复元素，默认删除最后一个元素。一次删不完，可以重复删除
# print(list2) #['dcs', 'xian', 10086, '10010']
# 5.根据索引进行删除del关键字
# list1 = ["dcs","xian",10086,"10010"]
# del list1 #删除索引为2的元素
# print(list1) #['dcs', 'xian', '10010']
# 6.pop()删除列表元素,()内不传入值，则默认删除列表最后的元素
# list1 = ["dcs","xian",10086,"10010"]
# print(list1.pop(2)) # 删除列表索引为2元素并打印
# print(list1) # ['dcs', 'xian', '10010']
# 使用切片对列表进行反转
# list1 = ["dcs","xian",10086,"10010"]
# print(list1[::-1]) # ['10010', 10086, 'xian', 'dcs']
# # reverse():使用函数对列表进行反转
# list1 = ["dcs","xian",10086,"10010"]
# list1.reverse()
# print(list1) #['10010', 10086, 'xian', 'dcs']
# 列表的排序
# 1.sort():对列表进行排序，只针对全部时int或者str类型的元素进行排序。不能混合
# list1 = ["dcs", "Xian", "10086", "10010"]
# list1.sort()
# print(list1) # (升序排列)#['10010', '10086', 'Xian', 'dcs']
# list1 = ['dcs', 'Xian', '10086', '10010']
# list1.sort(reverse=True)
# print(list1) # (降序排列)#['xian', 'dcs', '10086', '10010']
# 2.sorted():对列表进行排序，排序完成之后，会生成一个排序之后的新列表
# list1 =
# list2 = sorted(list1)
# print(list1) #
# print(list2) #
# list3 = sorted(list1,reverse=True) #降序排列加上reverse=True参数
# print(list3) #
# python中的字典# 1.给字典添加一个键值对
# dict1 = {"name":"xiaozhang","age":"18"}
# dict1["sex"] ="man"#如果字典中不存在sex键，则起到复制的作用。如果存在，则修改sex键的值
# print(dict1)#{'name': 'xiaozhang', 'age': '18', 'sex': 'man'}
# 2.取出字典中的键,通过for循环遍历字典中的键(key)
# dict1 = {"name":"xiaozhang","age":"18"}
# for i in dict1.keys(): # i:自定义的值 keys()是一个修饰函数,代表取字典中键
# print(i)# name，age
# 不加修饰函数遍历字典
# for i in dict1:# 不加任何修饰函数，则默认取得是字典中的键
# print(i) #name，age
# 3.取出字典中的值,遍历取值,取字典中所有的值
# dict1 = {"name":"xiaozhang","age":"18"}
# for i in dict1.values():#需要加上一个修饰函数values()来取值
# print(i)#xiaozhang，18
# 4.取出字典中特定的值，需要用键来取值
# dict1 = {"name":"xiaozhang","age":"18"}
# print(dict1["name"])#xiaozhang
# print(dict1["age"])#18
# 5.setdefault():给字典添加键值对
# dict1 = {"name":"xiaozhang","age":"18"}
# dict1.setdefault("sex","man")#通过setdefault()函数给字典中添加键值对#{'name': 'xiaozhang', 'age': '18', 'sex': 'man',
# dict1.setdefault("age","19")#如果添加的键在字典中，则不生效#{'name': 'xiaozhang', 'age': '18'}
# dict1.setdefault("class")# 如果只添加键的话，则默认值为None #{'name': 'xiaozhang', 'age': '18', 'class': None}
# print(dict1)
# 6.del：删除字典
# dict1 ={"name":"xiaozhang","age":"18"}
# del dict1# 删除dict1字典
# print(dict1) # name 'dict1' is not defined
# 7.删除键值对，根据键(key)来删除键值对
# dict1 ={"name":"xiaozhang","age":"18"}
# del dict1["name"]# 通过删除字典中的键"name"，删除整个键值对
# print(dict1) # {'age': '18'}
# 8.同时取字典中的键与值
# dict1 = {"name":"xiaozhang","age":"18"}
# 第一种同时取字典中的键与值的方法
# for i in dict1: #不加任何修饰函数，默认遍历字典中的键
# print(i,dict1) #name xiaozhang，age 18
# 第二种同时取字典中的键与值的方法
# for k,v in dict1.items(): #如果需要用两个变量分别接收键与值，则需要用到items()函数来进行修饰
# print(k,v)#name xiaozhang，age 18
# 9.pop()函数，删除指定的键并返回删除的值，通过key来删除值
# dict1 ={"name":"xiaozhang","age":"18"}
# print(dict1.pop("name"))#xiaozhang#打印被删除的值内容
# print(dict1)#{'age': '18'}
# 10.clear():清空字典中的所有项
# dict1 ={"name":"xiaozhang","age":"18"}
# dict1.clear()
# print(dict1)#{}
# 11.get()函数，可以通过字典中的key获取建键的值
# dict1 = {"name":"xiaozhang","age":"18"}
# value = dict1.get("name")
# print(value)#xiaozhang
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