Python字典增加键值对
类似于赋值,将值赋给不存在的键
代码:
person = {"name":"zhangsan", "age":18, "height":18}
print(person)
person["weight"] = "60kg"
print(person)
结果:
{‘name’: ‘zhangsan’, ‘age’: 18, ‘height’: 18}
{‘name’: ‘zhangsan’, ‘age’: 18, ‘height’: 18, ‘weight’: ’60kg’}
Python字典的删除键值对
有pop方法,popitem方法,clear方法与del(后两个不常用)
代码:
person = {"name":"zhangsan", "age":18, "height":18, "weight":"60kg"} person.pop("age") print(person) person.popitem() print(person) person.clear() print(person)
结果:
{‘name’: ‘zhangsan’, ‘height’: 18, ‘weight’: ’60kg’}
{‘name’: ‘zhangsan’, ‘height’: 18}
{}
Python字典修改键对应的值
和增加键的道理相同,为字典的键赋值,如果键存在则修改,不存在则添加
Python字典的查询
这里的查询指的是已知键查询对应的值
代码:
person = {"name":"zhangsan", "age":18, "height":18, "weight":"60kg"} print(person["name"]) #返回的结果就是zhangsan