python - 如何在python中找到list和dict之间的区别

Question

我有一个可以返回列表或字典的数组，如何找到差异？

前任：

val = { 'sum':'10', 'sub':'5', 'mul':'25', 'div':'1' }

（或者）

val = [ { 'sum':'10', 'sub':'5',  'mul':'25',  'div':'1' },
        { 'sum':'20', 'sub':'10', 'mul':'100', 'div':'1' }]

Answer 1

如果你只需要检查 dict 和 list，你可以使用isinstance

>>> val = { 'sum':'10', 'sub':'5', 'mul':'25', 'div':'1' }
>>> isinstance(val, list)
False
>>> isinstance(val, dict)
True
>>> 

Answer 2

如果您的问题是关于类型检查，那么您可以使用isinstance：

>>> val = { 'sum':'10', 'sub':'5', 'mul':'25', 'div':'1' }
>>> isinstance(val, dict)
True

>>> val = [ { 'sum':'10', 'sub':'5', 'mul':'25', 'div':'1' }, { 'sum':'20', 'sub':'10', 'mul':'100', 'div':'1' }]
>>> isinstance(val, list)
True

帮助isinstance：

>>> print isinstance.__doc__
isinstance(object, class-or-type-or-tuple) -> bool

Return whether an object is an instance of a class or of a subclass thereof.
With a type as second argument, return whether that is the object's type.
The form using a tuple, isinstance(x, (A, B, ...)), is a shortcut for
isinstance(x, A) or isinstance(x, B) or ... (etc.).

Answer 3

isinstance(val, dict)对比isinstance(val, list)