6、python的字典

python 字典

表现形式：键值对
定义符号：{}
键在一个字典中必须唯一，不能重复；若重复覆盖（修改）原来的值

字典中键，理论上来说，只要不唯一，可以随便搞，但是为了头发着想，还是悠着点!!! /(ㄒoㄒ)/~~

字典的基操

访问

a = {0:"apple" , 1:"huawei" , 2:"xiaomi"}
print(a[0])  # apple

添加

a = {0:"apple" , 1:"huawei" , 2:"xiaomi"}
a[3] = "祖安小王子的坟头蹦迪入场券*1"
print(a)  

空字典创建

a = {  }

修改

a = {0:"apple" , 1:"huawei" , 2:"xiaomi"}
a[0] = "泉水周围的地板，被你擦的很亮啊！(╬▔皿▔)凸"
print(a)  

删除

a = {0:"apple" , 1:"huawei" , 2:"xiaomi"}
del a[0]
print(a)

遍历字典

a = {0:"apple" , 1:"huawei" , 2:"xiaomi"}
for key ,value  in a.items() :
      print(key)
      print(value)
      print("-"*10)

遍历字典2 遍历所有键

a = {0:"apple" , 1:"huawei" , 2:"xiaomi"}
for key  in a.keys() :
      print(key)
      print("-"*10)

遍历字典3 遍历所有值

a = {0:"apple" , 1:"huawei" , 2:"xiaomi"}
for value  in a.values() :
      print(value)
      print("-"*10)