标签：hid closed lap open val close gif cli 赋值
一.字典的定义
在python中，字典数据类型使用{}来定义，在大括号中，存储的是键值对，即key:value的形式，并且key不能有重复值，如果有重复，后面的值会覆盖前面的；值可以重复
# 字典的定义 dict1 = {"name": "xiaoming", "age":18, "sex": "man"} print(dict1) 结果： {‘name‘: ‘xiaoming‘, ‘age‘: 18, ‘sex‘: ‘man‘}
二.字典的遍历
字典是无序的，所以不能像字符串，列表一样使用下标来遍历访问，那如何获取字典中的元素呢？
dict1 = {"name": "xiaoming", "age": 20, "sex": "man"}
# print(dict1.keys()) # .keys()获取所有的键
for key in dict1.keys():
print(key)
结果如下
name
age
sex
dict1 = {"name": "xiaoming", "age": 20, "sex": "man"}
# print(dict1.values()) # .values()获取所有的值
for value in dict1.values():
print(value)
结果如下
xiaoming
20
man
dict1 = {"name": "xiaoming", "age": 20, "sex": "man"}
# print(dict1.items()) # .items()获取所有的键值对
for i in dict1.items():
print(i[0], i[1])
结果如下
name xiaoming
age 20
sex man
三.字典的常见操作
dict1 ={ "name": "xiaoming", "age": 19, "sex": "man" } print("字典类型和长度".center(30, "=")) print(len(dict1)) print(type(dict1)) # dict的常见操作 # 添加成员，直接赋值新的成员 print("添加成员".center(30, "=")) dict1["phonenumber"] = "1234567890" print(dict1) # 删除成员 print("删除成员".center(30, "=")) del dict1["phonenumber"] print(dict1) dict1.pop("sex") print(dict1) # 查询成员 # 通过键找值 print("查询成员".center(30, "=")) value = dict1.get("name") print(value) list1 = dict1.keys() list2 = dict1.values() print(list1) print(list2) # 修改 print("修改成员".center(30, "=")) dict1["name"] = "xianowang" print(dict1) 结果如下 ===========字典类型和长度============ 3 <class ‘dict‘> =============添加成员============= {‘name‘: ‘xiaoming‘, ‘age‘: 19, ‘sex‘: ‘man‘, ‘phonenumber‘: ‘1234567890‘} =============删除成员============= {‘name‘: ‘xiaoming‘, ‘age‘: 19, ‘sex‘: ‘man‘} {‘name‘: ‘xiaoming‘, ‘age‘: 19} =============查询成员============= xiaoming dict_keys([‘name‘, ‘age‘]) dict_values([‘xiaoming‘, 19]) =============修改成员============= {‘name‘: ‘xianowang‘, ‘age‘: 19}
标签：hid closed lap open val close gif cli 赋值
原文地址：https://www.cnblogs.com/golinux/p/10781605.html
