标签：name 赋值 没有 none color 就是 pre update 报错
1. 有就覆盖，没有就添加
dic = {‘name‘: ‘老男孩‘, ‘age‘: 56, ‘hobby‘: ‘women‘}
dic[‘sex‘] = ‘LaddyBoy‘
dic[‘name‘] = ‘Alex‘
2. 有就不变，没有就添加
dic = {‘name‘: ‘老男孩‘, ‘age‘: 56, ‘hobby‘: ‘women‘}
dic.setdefault(‘sex‘, ‘Laddyboy‘)
dic.setdefault(‘name‘, ‘alex‘)
print(dic)
1. pop 按照Key删除 ， 有返回值，返回删除对应键的值。
dic = {‘name‘: ‘老男孩‘, ‘age‘: 56, ‘hobby‘: ‘women‘}
print(dic.pop(‘age‘))
print(dic.pop(‘age1‘, ‘没有此键...‘)) #如果没有会报错，但是加上值就是返回你写的值
print(dic)
2. clear 清空字典
dic = {‘name‘: ‘老男孩‘, ‘age‘: 56, ‘hobby‘: ‘women‘}
dic.clear()
print(dic)
3. pop.item 随机删除，有返回值，返回为元祖，里边是删除的键对值
dic = {‘name‘: ‘老男孩‘, ‘age‘: 56, ‘hobby‘: ‘women‘}
print(dic.popitem())
print(dic)
4. del 删除整个字典
按照键删除
dic = {‘name‘: ‘老男孩‘, ‘age‘: 56, ‘hobby‘: ‘women‘}
del dic[‘name‘]
print(dic)
1. dic[‘name‘] = ‘Alex‘ 有就覆盖没有就添加
2. update 两个字典的更新
dic = {"name": "jin", "age": 18, "sex": "male"} dic2 = {"name": "alex", "weight": 75} dic2.update(dic) # 将dic里面的所有键值对 覆盖添加到dic2中，dic不变 print(dic) # {‘name‘: ‘jin‘, ‘age‘: 18, ‘sex‘: ‘male‘} print(dic2) # {‘name‘: ‘jin‘, ‘weight‘: 75, ‘age‘: 18, ‘sex‘: ‘male‘}
1. 有就返回值，没有报错
# 1,dic[‘name‘] dic = {‘name‘: ‘老男孩‘, ‘age‘: 56, ‘hobby‘: ‘women‘} print(dic[‘name‘])
2. 有就返回值 ， 没有返回None
2,dic.get(‘name‘)
dic = {‘name‘: ‘老男孩‘, ‘age‘: 56, ‘hobby‘: ‘women‘}print(dic.get(‘name‘))
print(dic.get(‘name1‘))
print(dic.get(‘name1‘, ‘sb没有此键‘))
3. for循环查询
dic.keys(), dic.values(), dic.items() #类似于list但不是list的类型。
# 循环键
dic = {‘name‘: ‘老男孩‘, ‘age‘: 56, ‘hobby‘: ‘women‘}
for key in dic.keys():
print(key)
# 循环值
dic = {‘name‘: ‘老男孩‘, ‘age‘: 56, ‘hobby‘: ‘women‘}
for value in dic.values():
print(value)
# 循环 键 和 值 分别赋值
dic = {‘name‘: ‘老男孩‘, ‘age‘: 56, ‘hobby‘: ‘women‘}
for k,v in dic.items():
print(k,v)
标签：name 赋值 没有 none color 就是 pre update 报错
原文地址：https://www.cnblogs.com/luchenhui/p/8985508.html
