Python中创建字典的五种方式

# 字典的创建方式
# 方式一 {key: value}
dict1 = {'one': 1, 'two': 2, 'three': 3}
print(dict1)

# 方式二 dict(zip(keys, values))
# dict([(k, v), (k, v)])
dict2 = dict([('one', 1), ('two', 2), ('three', 3)])
print(dict2)

# dict(((k, v), (k, v)))
dict3 = dict((('one', 1), ('two', 2), ('three', 3)))
print(dict3)

# 方式三 dict(key=value)
dict4 = dict(one=1, two=2, three=3)
print(dict4)

# 方式四 字典推导式
lst1 = ['one', 'two', 'three']
lst2 = [1, 2, 3]
dict5 = {lst1[i]: lst2[i] for i in range(len(lst1))}
print(dict5)

# 方式五 fromkeys
# 没有指定value，默认None
dict6 = dict.fromkeys(['k1', 'k2', 'k3'])
print(dict6) # {'k1': None, 'k2': None, 'k3': None}

# 指定value
dict7 = dict.fromkeys(['k1', 'k2', 'k3'], 'value')
print(dict7) # {'k1': 'value', 'k2': 'value', 'k3': 'value'}